ovs-ofctl(8)

NAME
ovs-ofctl - administer OpenFlow switches

SYNOPSIS
ovs-ofctl [options] command [switch] [args...]

DESCRIPTION
The ovs-ofctl program is a command line tool for monitoring and administering OpenFlow switches. It can also show the current state of an OpenFlow switch, including features, configuration, and table entries. It should work with any OpenFlow switch, not just Open vSwitch.

  OpenFlow Switch Management Commands

These commands allow ovs-ofctl to monitor and administer an OpenFlow switch. It is able to show the current state of a switch, including features, configuration, and table entries.

Most of these commands take an argument that specifies the method for connecting to an OpenFlow switch. The following connection methods are supported:

    file
        This is short for unix:file, as long as file does not contain a colon.

    bridge
        This is short for unix:@RUNDIR@/bridge.mgmt, as long as bridge does not contain a colon.

    [type@]dp
        Attempts to look up the bridge associated with dp and open as above. If type is given, it specifies the datapath provider of dp, otherwise the default provider system is assumed.

show switch
    Prints to the console information on switch, including information on its flow tables and ports.

dump-tables switch
    Prints to the console statistics for each of the flow tables used by switch.

dump-ports switch [netdev]
    Prints to the console statistics for network devices associated with switch. If netdev is specified, only the statistics associated with that device will be printed. netdev can be an OpenFlow assigned port number or device name, e.g. eth0.

dump-ports-desc switch
    Prints to the console detailed information about network devices associated with switch (version 1.7 or later). This is a subset of the information provided by the show command.

mod-port switch port action
    Modify characteristics of port port in switch. port may be an OpenFlow port number or name or the keyword LOCAL (the preferred way to refer to the OpenFlow local port). The action may be any one of the following:
    Enable or disable the interface. This is equivalent to ifconfig up or ifconfig down on a Unix system.

    stp Enable or disable 802.1D spanning tree protocol (STP) on the interface. OpenFlow implementations that don't support STP will refuse to enable it.

    receive
        Enable or disable OpenFlow processing of packets received on this interface. When packet processing is disabled, packets will be dropped instead of being processed through the OpenFlow table. The receive or no-receive setting applies to all packets except 802.1D spanning tree packets, which are separately controlled by receive-stp or no-receive-stp.

    forward
        Allow or disallow forwarding of traffic to this interface. By default, forwarding is enabled.

    flood
        Controls whether an OpenFlow flood action will send traffic out this interface. By default, flooding is enabled. Disabling flooding is primarily useful to prevent loops when a spanning tree protocol is not in use.

    packet-in
        Controls whether packets received on this interface that do not match a flow table entry generate a ``packet in'' message to the OpenFlow controller. By default, ``packet in'' messages are enabled.

    The show command displays (among other information) the configuration that mod-port changes.

get-frags switch
    Prints switch's fragment handling mode. See set-frags, below, for a description of each fragment handling mode.

    The show command also prints the fragment handling mode among its other output.

set-frags switch frag_mode
    Configures switch's treatment of IPv4 and IPv6 fragments. The choices for frag_mode are:

    normal
        Fragments pass through the flow table like non-fragmented packets. The TCP ports, UDP ports, and ICMP type and code fields are always set to 0, even for fragments where that information would otherwise be available (fragments with offset 0). This is the default fragment handling mode for an OpenFlow switch.

    drop
        Fragments are dropped without passing through the flow table.

    reassemble
        The switch reassembles fragments into full IP packets before passing them through the flow table. Open vSwitch does not implement this fragment handling mode.

    nx-match
        Fragments pass through the flow table like non-fragmented packets. The TCP ports, UDP ports, and ICMP type and code fields are available for matching for fragments with offset 0, and set to 0 in fragments with nonzero offset. This mode is a Nicira extension.

    See the description of ip_frag, below, for a way to match on whether a packet is a fragment and on its fragment offset.

dump-flows switch [flows]
    Prints to the console all flow entries in switch's tables that match flows. If flows is omitted, all flows in the switch are retrieved. See Flow Syntax, below, for the syntax of flows. The output format is described in Table Entry Output.

    By default, ovs-ofctl prints flow entries in the same order that the switch sends them, which is unlikely to be intuitive or consistent. See the description of --sort and --rsort, under OPTIONS below, to influence the display order.

dump-aggregate switch [flows]
    Prints to the console aggregate statistics for flows in switch's tables that match flows. If flows is omitted, the statistics are aggregated across all flows in the switch's flow tables. See Flow Syntax, below, for the syntax of flows. The output format is described in Table Entry Output.

queue-stats switch [port [queue]]
    Prints to the console statistics for the specified queue on port within switch. port can be an OpenFlow port number or name, the keyword LOCAL (the preferred way to refer to the OpenFlow local port), or the keyword ALL. Either of port or queue or both may be omitted (or equivalently the keyword ALL). If both are omitted, statistics are printed for all queues on all ports. If only queue is omitted, then statistics are printed for all queues on port; if only port is omitted, then statistics are printed for queue on every port where it exists.

  OpenFlow Switch Flow Table Commands
These commands manage the flow table in an OpenFlow switch. In each case, flow specifies a flow entry in the format described in Flow Syntax, below, and file is a text file that contains zero or more flows in the same syntax, one per line.

add-flow switch flow
    Add each flow entry to switch's tables.

[--strict] mod-flows switch flow
    Modify the actions in entries from switch's tables that match the specified flows. With --strict, wildcards are not treated as active for matching purposes.

del-flows switch
    Deletes entries from switch's flow table. With only a switch argument, deletes all flows. Otherwise, deletes flow entries that match the specified flows. With --strict, wildcards are not treated as active for matching purposes.

[--readd] replace-flows switch file
    Reads flow entries from file (or stdin if file is -) and queries the flow table from switch. Then it fixes up any differences, adding flows from flow that are missing on switch, deleting flows from switch that are not in file, and updating flows in switch whose actions, cookie, or timeouts differ in file.

    With --readd, ovs-ofctl adds all the flows from file, even those that exist with the same actions, cookie, and timeout in switch. This resets all the flow packet and byte counters to 0, which can be useful for debugging.

diff-flows source1 source2
    Reads flow entries from source1 and source2 and prints the differences. A flow that is in source1 but not in source2 is printed preceded by a -, and a flow that is in source2 but not in source1 is printed preceded by a +. If a flow exists in both source1 and source2 with different actions, cookie, or timeouts, then both versions are printed preceded by - and +, respectively.

    source1 and source2 may each name a file or a switch. If a name begins with / or ., then it is considered to be a file name. A name that contains : is considered to be a switch. Otherwise, it is a file if a file by that name exists, a switch if not.

    For this command, an exit status of 0 means that no differences were found, 1 means that an error occurred, and 2 means that some differences were found.

packet-out switch in_port actions packet...
    Connects to switch and instructs it to execute the OpenFlow actions on each packet. For the purpose of executing the actions, the packets are considered to have arrived on in_port, which may be an OpenFlow port number or name (e.g. eth0), the keyword LOCAL (the preferred way to refer to the OpenFlow ``local'' port), or the keyword NONE to indicate that the packet was generated by the switch itself.

  OpenFlow Switch Monitoring Commands

snoop switch
    Connects to switch and prints to the console all OpenFlow messages received. Unlike other ovs-ofctl commands, if switch is the name of a bridge, then the snoop command connects to a Unix domain socket named @RUNDIR@/bridge.snoop. ovs-vswitchd listens on such a socket for each bridge and sends to it all of the OpenFlow messages sent to or received from its configured OpenFlow controller. Thus, this command can be used to view OpenFlow protocol activity between a switch and its controller.

    When a switch has more than one controller configured, only the traffic to and from a single controller is output. If none of the controllers is configured as a master or a slave (using a Nicira extension to OpenFlow), then a controller is chosen arbitrarily among them. If there is a master controller, it is chosen; otherwise, if there are any controllers that are not masters or slaves, one is chosen arbitrarily; otherwise, a slave controller is chosen arbitrarily. This choice is made once at connection time and does not change as controllers reconfigure their roles.

    If a switch has no controller configured, or if the configured controller is disconnected, no traffic is sent, so monitoring will not show any traffic.

monitor switch [miss-len] [invalid_ttl] [watch:[spec...]]
    Connects to switch and prints to the console all OpenFlow messages received. Usually, switch should specify the name of a bridge in the ovs-vswitchd database.

    If miss-len is provided, ovs-ofctl sends an OpenFlow ``set configuration'' message at connection setup time that requests miss-len bytes of each packet that misses the flow table. Open vSwitch does not send these and other asynchronous messages to an ovs-ofctl monitor client connection unless a nonzero value is specified on this argument. (Thus, if miss-len is not specified, very little traffic will ordinarily be printed.)

    If invalid_ttl is passed, ovs-ofctl sends an OpenFlow ``set configuration'' message at connection setup time that requests INVALID_TTL_TO_CONTROLLER, so that ovs-ofctl monitor can receive ``packet-in'' messages when TTL reaches zero on dec_ttl action.

    watch:[spec...] causes ovs-ofctl to send a ``monitor request'' Nicira extension message to the switch at connection setup time. This message causes the switch to send information about flow table changes as they occur. The following comma-separated spec syntax is available:

    !initial
        Do not report the switch's initial flow table contents.

    !add
        Do not report newly added flows.

    !delete
        Do not report deleted flows.

    !modify
        Do not report modifications to existing flows.

    !own
        Abbreviate changes made to the flow table by ovs-ofctl's own connection to the switch. (These could only occur using the ofctl/send command described below under RUNTIME MANAGEMENT COMMANDS.)

    !actions
        Do not report actions as part of flow updates.

    table=number
        Limits the monitoring to the table with the given number between 0 and 254. By default, all tables are monitored.

    out_port=port
        If set, only flows that output to port are monitored. The port may be an OpenFlow port number or keyword (e.g. LOCAL).

    field=value
        Monitors only flows that have field specified as the given value. Any syntax valid for matching on dump-flows may be used.

    This command may be useful for debugging switch or controller implementations. With watch:, it is particularly useful for observing how a controller updates flow tables.

  OpenFlow Switch and Controller Commands
The following commands, like those in the previous section, may be applied to OpenFlow switches, using any of the connection methods described in that section. Unlike those commands, these may also be applied to OpenFlow controllers.

probe target
    Sends a single OpenFlow echo-request message to target and waits for the response. With the -t or --timeout option, this command can test whether an OpenFlow switch or controller is up and running.

ping target [n]
    Sends a series of 10 echo request packets to target and times each reply. The echo request packets consist of an OpenFlow header plus n bytes (default: 64) of randomly generated payload. This measures the latency of individual requests.

benchmark target n count
    Sends count echo request packets that each consist of an OpenFlow header plus n bytes of payload and waits for each response. Reports the total time required. This is a measure of the maximum bandwidth to target for round-trips of n-byte messages.

  Other Commands

ofp-parse file
    Reads file (or stdin if file is -) as a series of OpenFlow messages in the binary format used on an OpenFlow connection, and prints them to the console. This can be useful for printing OpenFlow messages captured from a TCP stream.

  Flow Syntax

Some ovs-ofctl commands accept an argument that describes a flow or flows. Such flow descriptions comprise a series field=value assignments, separated by commas or white space. (Embedding spaces into a flow description normally requires quoting to prevent the shell from breaking the description into multiple arguments.)

Flow descriptions should be in normal form. This means that a flow may only specify a value for an L3 field if it also specifies a particular L2 protocol, and that a flow may only specify an L4 field if it also specifies particular L2 and L3 protocol types. For example, if the L2 protocol type dl_type is wildcarded, then L3 fields nw_src, nw_dst, and nw_proto must also be wildcarded. Similarly, if dl_type or nw_proto (the L3 protocol type) is wildcarded, so must be tp_dst and tp_src, which are L4 fields. ovs-ofctl will warn about flows not in normal form.

The following field assignments describe how a flow matches a packet. If any of these assignments is omitted from the flow syntax, the field is treated as a wildcard; thus, if all of them are omitted, the resulting flow matches all packets. The string * may be specified to explicitly mark any of these fields as a wildcard. (* should be quoted to protect it from shell expansion.)

in_port=port
    Matches OpenFlow port port, which may be an OpenFlow port number or keyword (e.g. LOCAL). ovs-ofctl show.

    (The resubmit action can search OpenFlow flow tables with arbitrary in_port values, so flows that match port numbers that do not exist from an OpenFlow perspective can still potentially be matched.)

dl_vlan=vlan
    Matches IEEE 802.1q Virtual LAN tag vlan. Specify 0xffff as vlan to match packets that are not tagged with a Virtual LAN; otherwise, specify a number between 0 and 4095, inclusive, as the 12-bit VLAN ID to match.

dl_vlan_pcp=priority
    Matches IEEE 802.1q Priority Code Point (PCP) priority, which is specified as a value between 0 and 7, inclusive. A higher value indicates a higher frame priority level.

dl_src=xx:xx:xx:xx:xx:xx
    Matches an Ethernet source (or destination) address specified as 6 pairs of hexadecimal digits delimited by colons (e.g. 00:0A:E4:25:6B:B0).

dl_src=xx:xx:xx:xx:xx:xx/xx:xx:xx:xx:xx:xx
    Matches an Ethernet destination address specified as 6 pairs of hexadecimal digits delimited by colons (e.g. 00:0A:E4:25:6B:B0), with a wildcard mask following the slash. Open vSwitch 1.8 and later support arbitrary masks for source and/or destination. Earlier versions only support masking the destination with the following masks:

    01:00:00:00:00:00
        Match only the multicast bit. Thus, dl_dst=01:00:00:00:00:00/01:00:00:00:00:00 matches all multicast (including broadcast) Ethernet packets, and dl_dst=00:00:00:00:00:00/01:00:00:00:00:00 matches all unicast Ethernet packets.

    fe:ff:ff:ff:ff:ff
        Match all bits except the multicast bit. This is probably not useful.

    ff:ff:ff:ff:ff:ff
        Exact match (equivalent to omitting the mask).

    00:00:00:00:00:00
        Wildcard all bits (equivalent to dl_dst=*.)

dl_type=ethertype
    Matches Ethernet protocol type ethertype, which is specified as an integer between 0 and 65535, inclusive, either in decimal or as a hexadecimal number prefixed by 0x (e.g. 0x0806 to match ARP packets).

nw_src=ip[/netmask]
    When dl_type is 0x0800 (possibly via shorthand, e.g. ip or tcp), matches IPv4 source (or destination) address ip, which may be specified as an IP address or host name (e.g. 192.168.1.1 or www.example.com). The optional netmask allows restricting a match to an IPv4 address prefix. The netmask may be specified as a dotted quad (e.g. 192.168.1.0/255.255.255.0) or as a CIDR block (e.g. 192.168.1.0/24). Open vSwitch 1.8 and later support arbitrary dotted quad masks; earlier versions support only CIDR masks, that is, the dotted quads that are equivalent to some CIDR block.

    When dl_type=0x0806 or arp is specified, matches the ar_spa or ar_tpa field, respectively, in ARP packets for IPv4 and Ethernet.

    When dl_type=0x8035 or rarp is specified, matches the ar_spa or ar_tpa field, respectively, in RARP packets for IPv4 and Ethernet.

    When dl_type is wildcarded or set to a value other than 0x0800, 0x0806, or 0x8035, the values of nw_src and nw_dst are ignored (see Flow Syntax above).

nw_proto=proto
    When ip or dl_type=0x0800 is specified, matches IP protocol type proto, which is specified as a decimal number between 0 and 255, inclusive (e.g. 1 to match ICMP packets or 6 to match TCP packets).

    When ipv6 or dl_type=0x86dd is specified, matches IPv6 header type proto, which is specified as a decimal number between 0 and 255, inclusive (e.g. 58 to match ICMPv6 packets or 6 to match TCP). The header type is the terminal header as described in the DESIGN document.

    When arp or dl_type=0x0806 is specified, matches the lower 8 bits of the ARP opcode. ARP opcodes greater than 255 are treated as 0.

    When rarp or dl_type=0x8035 is specified, matches the lower 8 bits of the ARP opcode. ARP opcodes greater than 255 are treated as 0.

    When dl_type is wildcarded or set to a value other than 0x0800, 0x0806, 0x8035 or 0x86dd, the value of nw_proto is ignored (see Flow Syntax above).

nw_tos=tos
    Matches IP ToS/DSCP or IPv6 traffic class field tos, which is specified as a decimal number between 0 and 255, inclusive. Note that the two lower reserved bits are ignored for matching purposes.

    When dl_type is wildcarded or set to a value other than 0x0800 or 0x86dd, the value of nw_tos is ignored (see Flow Syntax above).

nw_ecn=ecn
    Matches ecn bits in IP ToS or IPv6 traffic class fields, which is specified as a decimal number between 0 and 3, inclusive.

    When dl_type is wildcarded or set to a value other than 0x0800 or 0x86dd, the value of nw_ecn is ignored (see Flow Syntax above).

nw_ttl=ttl
    Matches IP TTL or IPv6 hop limit value ttl, which is specified as a decimal number between 0 and 255, inclusive.

    When dl_type is wildcarded or set to a value other than 0x0800 or 0x86dd, the value of nw_ttl is ignored (see Flow Syntax above).

tp_src=port
    When dl_type and nw_proto specify TCP or UDP or SCTP, tp_src and tp_dst match the UDP or TCP or SCTP source or destination port port, respectively, which is specified as a decimal number between 0 and 65535, inclusive (e.g. 80 to match packets originating from a HTTP server).

    When dl_type and nw_proto take other values, the values of these settings are ignored (see Flow Syntax above).

tp_src=port/mask
    Bitwise match on TCP (or UDP or SCTP) source or destination port, respectively. The port and mask are 16-bit numbers written in decimal or in hexadecimal prefixed by 0x. Each 1-bit in mask requires that the corresponding bit in port must match. Each 0-bit in mask causes the corresponding bit to be ignored.

    Bitwise matches on transport ports are rarely useful in isolation, but a group of them can be used to reduce the number of flows required to match on a range of transport ports. For example, suppose that the goal is to match TCP source ports 1000 to 1999, inclusive. One way is to insert 1000 flows, each of which matches on a single source port. Another way is to look at the binary representations of 1000 and 1999, as follows:
    01111101000
    11111001111
    and then to transform those into a series of bitwise matches that accomplish the same results:
    01111101xxx
    0111111xxxx
    10xxxxxxxxx
    110xxxxxxxx
    1110xxxxxxx
    11110xxxxxx
    1111100xxxx
    which become the following when written in the syntax required by ovs-ofctl:
    tcp,tp_src=0x03e8/0xfff8
    tcp,tp_src=0x03f0/0xfff0
    tcp,tp_src=0x0400/0xfe00
    tcp,tp_src=0x0600/0xff00
    tcp,tp_src=0x0700/0xff80
    tcp,tp_src=0x0780/0xffc0
    tcp,tp_src=0x07c0/0xfff0

    Only Open vSwitch 1.6 and later supports bitwise matching on transport ports.

    Like the exact-match forms of tp_src and tp_dst described above, the bitwise match forms apply only when dl_type and nw_proto specify TCP or UDP or SCTP.

icmp_type=type
    When dl_type and nw_proto specify ICMP or ICMPv6, type matches the ICMP type and code matches the ICMP code. Each is specified as a decimal number between 0 and 255, inclusive.

    When dl_type and nw_proto take other values, the values of these settings are ignored (see Flow Syntax above).

table=number
    If specified, limits the flow manipulation and flow dump commands to only apply to the table with the given number between 0 and 254. Behavior varies if table is not specified (equivalent to specifying 255 as number). For flow table modification commands without --strict, the switch will choose the table for these commands to operate on. For flow table modification commands with --strict, the command will operate on any single matching flow in any table; it will do nothing if there are matches in more than one table. The dump-flows and dump-aggregate commands will gather statistics about flows from all tables.

    When this field is specified in add-flow, add-flows, mod-flows and del-flows commands, it activates a Nicira extension to OpenFlow, which as of this writing is only known to be implemented by Open vSwitch.

metadata=value[/mask]
    Matches value either exactly or with optional mask in the metadata field. value and mask are 64-bit integers, by default in decimal (use a 0x prefix to specify hexadecimal). Arbitrary mask values are allowed: a 1-bit in mask indicates that the corresponding bit in value must match exactly, and a 0-bit wildcards that bit. Matching on metadata was added in Open vSwitch 1.8.

The following shorthand notations are also available:

ip  Same as dl_type=0x0800.

icmp
    Same as dl_type=0x0800,nw_proto=1.

tcp Same as dl_type=0x0800,nw_proto=6.

udp Same as dl_type=0x0800,nw_proto=17.

sctp
    Same as dl_type=0x0800,nw_proto=132.

arp Same as dl_type=0x0806.

rarp
    Same as dl_type=0x8035.

The following field assignments require support for the NXM (Nicira Extended Match) extension to OpenFlow. When one of these is specified, ovs-ofctl will automatically attempt to negotiate use of this extension. If the switch does not support NXM, then ovs-ofctl will report a fatal error.

vlan_tci=tci[/mask]
    Matches modified VLAN TCI tci. If mask is omitted, tci is the exact VLAN TCI to match; if mask is specified, then a 1-bit in mask indicates that the corresponding bit in tci must match exactly, and a 0-bit wildcards that bit. Both tci and mask are 16-bit values that are decimal by default; use a 0x prefix to specify them in hexadecimal.

    The value that vlan_tci matches against is 0 for a packet that has no 802.1Q header. Otherwise, it is the TCI value from the 802.1Q header with the CFI bit (with value 0x1000) forced to 1.

    Examples:

    vlan_tci=0
        Match only packets without an 802.1Q header.

    vlan_tci=0xf123
        Match packets tagged with priority 7 in VLAN 0x123.

    vlan_tci=0x1123/0x1fff
        Match packets tagged with VLAN 0x123 (and any priority).

    vlan_tci=0x5000/0xf000
        Match packets tagged with priority 2 (in any VLAN).

    vlan_tci=0/0xfff
        Match packets with no 802.1Q header or tagged with VLAN 0 (and any priority).

    vlan_tci=0x5000/0xe000
        Match packets with no 802.1Q header or tagged with priority 2 (in any VLAN).

    vlan_tci=0/0xefff
        Match packets with no 802.1Q header or tagged with VLAN 0 and priority 0.

    Some of these matching possibilities can also be achieved with dl_vlan and dl_vlan_pcp.

ip_frag=frag_type
    When dl_type specifies IP or IPv6, frag_type specifies what kind of IP fragments or non-fragments to match. The following values of frag_type are supported:

    no  Matches only non-fragmented packets.

    yes Matches all fragments.

    first
        Matches only fragments with offset 0.

    later
        Matches only fragments with nonzero offset.

    not_later
        Matches non-fragmented packets and fragments with zero offset.

    The ip_frag match type is likely to be most useful in nx-match mode. See the description of the set-frags command, above, for more details.

arp_sha=xx:xx:xx:xx:xx:xx
    When dl_type specifies either ARP or RARP, arp_sha and arp_tha match the source and target hardware address, respectively. An address is specified as 6 pairs of hexadecimal digits delimited by colons.

ipv6_src=ipv6[/netmask]
    When dl_type is 0x86dd (possibly via shorthand, e.g., ipv6 or tcp6), matches IPv6 source (or destination) address ipv6, which may be specified as defined in RFC 2373. The preferred format is x:x:x:x:x:x:x:x, where x are the hexadecimal values of the eight 16-bit pieces of the address. A single instance of :: may be used to indicate multiple groups of 16-bits of zeros. The optional netmask allows restricting a match to an IPv6 address prefix. A netmask is specified as an IPv6 address (e.g. 2001:db8:3c4d:1::/ffff:ffff:ffff:ffff::) or a CIDR block (e.g. 2001:db8:3c4d:1::/64). Open vSwitch 1.8 and later support arbitrary masks; earlier versions support only CIDR masks, that is, CIDR block and IPv6 addresses that are equivalent to CIDR blocks.

ipv6_label=label
    When dl_type is 0x86dd (possibly via shorthand, e.g., ipv6 or tcp6), matches IPv6 flow label label.

nd_target=ipv6[/netmask]
    When dl_type, nw_proto, and icmp_type specify IPv6 Neighbor Discovery (ICMPv6 type 135 or 136), matches the target address ipv6. ipv6 is in the same format described earlier for the ipv6_src and ipv6_dst fields.

nd_sll=xx:xx:xx:xx:xx:xx
    When dl_type, nw_proto, and icmp_type specify IPv6 Neighbor Solicitation (ICMPv6 type 135), matches the source link-layer address option. An address is specified as 6 pairs of hexadecimal digits delimited by colons.

nd_tll=xx:xx:xx:xx:xx:xx
    When dl_type, nw_proto, and icmp_type specify IPv6 Neighbor Advertisement (ICMPv6 type 136), matches the target link-layer address option. An address is specified as 6 pairs of hexadecimal digits delimited by colons.

tun_id=tunnel-id[/mask]
    Matches tunnel identifier tunnel-id. Only packets that arrive over a tunnel that carries a key (e.g. GRE with the RFC 2890 key extension and a nonzero key value) will have a nonzero tunnel ID. If mask is omitted, tunnel-id is the exact tunnel ID to match; if mask is specified, then a 1-bit in mask indicates that the corresponding bit in tunnel-id must match exactly, and a 0-bit wildcards that bit.

tun_src=ip[/netmask]
    Matches tunnel IPv4 source (or destination) address ip. Only packets that arrive over a tunnel will have nonzero tunnel addresses. The address may be specified as an IP address or host name (e.g. 192.168.1.1 or www.example.com). The optional netmask allows restricting a match to a masked IPv4 address. The netmask may be specified as a dotted quad (e.g. 192.168.1.0/255.255.255.0) or as a CIDR block (e.g. 192.168.1.0/24).

regidx=value[/mask]
    Matches value either exactly or with optional mask in register number idx. The valid range of idx depends on the switch. value and mask are 32-bit integers, by default in decimal (use a 0x prefix to specify hexadecimal). Arbitrary mask values are allowed: a 1-bit in mask indicates that the corresponding bit in value must match exactly, and a 0-bit wildcards that bit.

    When a packet enters an OpenFlow switch, all of the registers are set to 0. Only explicit Nicira extension actions change register values.

pkt_mark=value[/mask]
    Matches packet metadata mark value either exactly or with optional mask. The mark is associated data that may be passed into other system components in order to facilitate interaction between subsystems. On Linux this corresponds to the skb mark but the exact implementation is platform-dependent.

Defining IPv6 flows (those with dl_type equal to 0x86dd) requires support for NXM. The following shorthand notations are available for IPv6-related flows:

ipv6
    Same as dl_type=0x86dd.

tcp6
    Same as dl_type=0x86dd,nw_proto=6.

udp6
    Same as dl_type=0x86dd,nw_proto=17.

sctp6
    Same as dl_type=0x86dd,nw_proto=132.

icmp6
    Same as dl_type=0x86dd,nw_proto=58.

Finally, field assignments to duration, n_packets, or n_bytes are ignored to allow output from the dump-flows command to be used as input for other commands that parse flows.

The add-flow, add-flows, and mod-flows commands require an additional field, which must be the final field specified:

actions=[target][,target...]
    Specifies a comma-separated list of actions to take on a packet when the flow entry matches. If no target is specified, then packets matching the flow are dropped. The target may be an OpenFlow port number designating the physical port on which to output the packet, or one of the following keywords:

    output:port
        Outputs the packet to port, which must be an OpenFlow port number or keyword (e.g. LOCAL).

    output:src[start..end]
        Outputs the packet to the OpenFlow port number read from src, which must be an NXM field as described above. For example, output:NXM_NX_REG0[16..31] outputs to the OpenFlow port number written in the upper half of register 0. This form of output uses an OpenFlow extension that is not supported by standard OpenFlow switches.

    enqueue:port:queue
        Enqueues the packet on the specified queue within port port, which must be an OpenFlow port number or keyword (e.g. LOCAL).. The number of supported queues depends on the switch; some OpenFlow implementations do not support queuing at all.

    normal
        Subjects the packet to the device's normal L2/L3 processing. (This action is not implemented by all OpenFlow switches.)

    flood
        Outputs the packet on all switch physical ports other than the port on which it was received and any ports on which flooding is disabled (typically, these would be ports disabled by the IEEE 802.1D spanning tree protocol).

    all Outputs the packet on all switch physical ports other than the port on which it was received.

    controller(key=value...)
        Sends the packet to the OpenFlow controller as a ``packet in'' message. The supported key-value pairs are:

        max_len=nbytes
            Limit to nbytes the number of bytes of the packet to send to the controller. By default the entire packet is sent.

        reason=reason
            Specify reason as the reason for sending the message in the ``packet in'' message. The supported reasons are action (the default), no_match, and invalid_ttl.

        id=controller-id
            Specify controller-id, a 16-bit integer, as the connection ID of the OpenFlow controller or controllers to which the ``packet in'' message should be sent. The default is zero. Zero is also the default connection ID for each controller connection, and a given controller connection will only have a nonzero connection ID if its controller uses the NXT_SET_CONTROLLER_ID Nicira extension to OpenFlow.
    Any reason other than action and any nonzero controller-id uses a Nicira vendor extension that, as of this writing, is only known to be implemented by Open vSwitch (version 1.6 or later).

    controller
        Shorthand for controller() or controller(max_len=nbytes), respectively.

    local
        Outputs the packet on the ``local port,'' which corresponds to the network device that has the same name as the bridge.

    in_port
        Outputs the packet on the port from which it was received.

    drop
        Discards the packet, so no further processing or forwarding takes place. If a drop action is used, no other actions may be specified.

    mod_vlan_vid:vlan_vid
        Modifies the VLAN id on a packet. The VLAN tag is added or modified as necessary to match the value specified. If the VLAN tag is added, a priority of zero is used (see the mod_vlan_pcp action to set this).

    mod_vlan_pcp:vlan_pcp
        Modifies the VLAN priority on a packet. The VLAN tag is added or modified as necessary to match the value specified. Valid values are between 0 (lowest) and 7 (highest). If the VLAN tag is added, a vid of zero is used (see the mod_vlan_vid action to set this).

    strip_vlan
        Strips the VLAN tag from a packet if it is present.

    push_vlan:ethertype
        Push a new VLAN tag onto the packet. Ethertype is used as the the Ethertype for the tag. Only ethertype 0x8100 should be used. (0x88a8 which the spec allows isn't supported at the moment.) A priority of zero and the tag of zero are used for the new tag.

    push_mpls:ethertype
        If the packet does not already contain any MPLS labels, changes the packet's Ethertype to ethertype, which must be either the MPLS unicast Ethertype 0x8847 or the MPLS multicast Ethertype 0x8848, and then pushes an initial label stack entry. The label stack entry's default label is 2 if the packet contains IPv6 and 0 otherwise, its default traffic control value is the low 3 bits of the packet's DSCP value (0 if the packet is not IP), and its TTL is copied from the IP TTL (64 if the packet is not IP).

        If the packet does already contain an MPLS label, pushes a new outermost label as a copy of the existing outermost label.

        There are some limitations in the implementation. push_mpls followed by another push_mpls will result in the first push_mpls being discarded.

    pop_mpls:ethertype
        Strips the outermost MPLS label stack entry. Currently the implementation restricts ethertype to a non-MPLS Ethertype and thus pop_mpls should only be applied to packets with an MPLS label stack depth of one.

        There are some limitations in the implementation. pop_mpls followed by another push_mpls without an intermediate push_mpls will result in the first push_mpls being discarded.

    mod_dl_src:mac
        Sets the source Ethernet address to mac.

    mod_dl_dst:mac
        Sets the destination Ethernet address to mac.

    mod_nw_src:ip
        Sets the IPv4 source address to ip.

    mod_nw_dst:ip
        Sets the IPv4 destination address to ip.

    mod_tp_src:port
        Sets the TCP or UDP or SCTP source port to port.

    mod_tp_dst:port
        Sets the TCP or UDP or SCTP destination port to port.

    mod_nw_tos:tos
        Sets the IPv4 ToS/DSCP field to tos, which must be a multiple of 4 between 0 and 255. This action does not modify the two least significant bits of the ToS field (the ECN bits).

    The following actions are Nicira vendor extensions that, as of this writing, are only known to be implemented by Open vSwitch:

    resubmit:port
        Re-searches this OpenFlow flow table (or the table whose number is specified by table) with the in_port field replaced by port (if port is specified) and executes the actions found, if any, in addition to any other actions in this flow entry.

        Recursive resubmit actions are obeyed up to an implementation-defined maximum depth. Open vSwitch 1.0.1 and earlier did not support recursion; Open vSwitch before 1.2.90 did not support table.

    set_tunnel:id
        If outputting to a port that encapsulates the packet in a tunnel and supports an identifier (such as GRE), sets the identifier to id. If the set_tunnel form is used and id fits in 32 bits, then this uses an action extension that is supported by Open vSwitch 1.0 and later. Otherwise, if id is a 64-bit value, it requires Open vSwitch 1.1 or later.

    set_queue:queue
        Sets the queue that should be used to queue when packets are output. The number of supported queues depends on the switch; some OpenFlow implementations do not support queuing at all.

    pop_queue
        Restores the queue to the value it was before any set_queue actions were applied.

    dec_ttl
        Decrement TTL of IPv4 packet or hop limit of IPv6 packet. If the TTL or hop limit is initially zero, no decrement occurs. Instead, a ``packet-in'' message with reason code OFPR_INVALID_TTL is sent to each connected controller that has enabled receiving them, if any. Processing the current set of actions then stops. However, if the current set of actions was reached through ``resubmit'' then remaining actions in outer levels resume processing. This action also optionally supports the ability to specify a list of valid controller ids. Each of controllers in the list will receive the ``packet_in'' message only if they have registered to receive the invalid ttl packets. If controller ids are not specified, the ``packet_in'' message will be sent only to the controllers having controller id zero which have registered for the invalid ttl packets.

    set_mpls_ttl:ttl
        Set the TTL of the outer MPLS label stack entry of a packet. ttl should be in the range 0 to 255 inclusive.

    dec_mpls_ttl
        Decrement TTL of the outer MPLS label stack entry of a packet. If the TTL is initially zero, no decrement occurs. Instead, a ``packet-in'' message with reason code OFPR_INVALID_TTL is sent to each connected controller with controller id zer that has enabled receiving them. Processing the current set of actions then stops. However, if the current set of actions was reached through ``resubmit'' then remaining actions in outer levels resume processing.

    note:[hh]...
        Does nothing at all. Any number of bytes represented as hex digits hh may be included. Pairs of hex digits may be separated by periods for readability. The note action's format doesn't include an exact length for its payload, so the provided bytes will be padded on the right by enough bytes with value 0 to make the total number 6 more than a multiple of 8.

    move:src[start..end]->dst[start..end]
        Copies the named bits from field src to field dst. src and dst must be NXM field names as defined in nicira-ext.h, e.g. NXM_OF_UDP_SRC or NXM_NX_REG0. Each start and end pair, which are inclusive, must specify the same number of bits and must fit within its respective field. Shorthands for [start..end] exist: use [bit] to specify a single bit or [] to specify an entire field.

        Examples: move:NXM_NX_REG0[0..5]->NXM_NX_REG1[26..31] copies the six bits numbered 0 through 5, inclusive, in register 0 into bits 26 through 31, inclusive; move:NXM_NX_REG0[0..15]->NXM_OF_VLAN_TCI[] copies the least significant 16 bits of register 0 into the VLAN TCI field.

    load:value->dst[start..end]
        Writes value to bits start through end, inclusive, in field dst.

        Example: load:55->NXM_NX_REG2[0..5] loads value 55 (bit pattern 110111) into bits 0 through 5, inclusive, in register 2.

    push:src[start..end]
        Pushes start to end bits inclusive, in fields on top of the stack.

        Example: push:NXM_NX_REG2[0..5] push the value stored in register 2 bits 0 through 5, inclusive, on to the internal stack.

    pop:dst[start..end]
        Pops from the top of the stack, retrieves the start to end bits inclusive, from the value popped and store them into the corresponding bits in dst.

        Example: pop:NXM_NX_REG2[0..5] pops the value from top of the stack. Set register 2 bits 0 through 5, inclusive, based on bits 0 through 5 from the value just popped.

    set_field:value->dst
        Writes the literal value into the field dst, which should be specified as a name used for matching. (This is similar to load but more closely matches the set-field action defined in Open Flow 1.2 and above.)

        Example: set_field:00:11:22:33:44:55->eth_src.

    multipath(fields, basis, algorithm, n_links, arg, dst[start..end])
        Hashes fields using basis as a universal hash parameter, then the applies multipath link selection algorithm (with parameter arg) to choose one of n_links output links numbered 0 through n_links minus 1, and stores the link into dst[start..end], which must be an NXM field as described above.

        Currently, fields must be either eth_src or symmetric_l4 and algorithm must be one of modulo_n, hash_threshold, hrw, and iter_hash. Only the iter_hash algorithm uses arg.

        Refer to nicira-ext.h for more details.

    bundle(fields, basis, algorithm, slave_type, slaves:[s1, s2, ...])
        Hashes fields using basis as a universal hash parameter, then applies the bundle link selection algorithm to choose one of the listed slaves represented as slave_type. Currently the only supported slave_type is ofport. Thus, each s1 through sN should be an OpenFlow port number. Outputs to the selected slave.

        Currently, fields must be either eth_src or symmetric_l4 and algorithm must be one of hrw and active_backup.

        Example: bundle(eth_src,0,hrw,ofport,slaves:4,8) uses an Ethernet source hash with basis 0, to select between OpenFlow ports 4 and 8 using the Highest Random Weight algorithm.

        Refer to nicira-ext.h for more details.

    bundle_load(fields, basis, algorithm, slave_type, dst[start..end], slaves:[s1, s2, ...])
        Has the same behavior as the bundle action, with one exception. Instead of outputting to the selected slave, it writes its selection to dst[start..end], which must be an NXM field as described above.

        Example: bundle_load(eth_src, 0, hrw, ofport, NXM_NX_REG0[], slaves:4, 8) uses an Ethernet source hash with basis 0, to select between OpenFlow ports 4 and 8 using the Highest Random Weight algorithm, and writes the selection to NXM_NX_REG0[].

        Refer to nicira-ext.h for more details.

    learn(argument[,argument]...)
        This action adds or modifies a flow in an OpenFlow table, similar to ovs-ofctl --strict mod-flows. The arguments specify the flow's match fields, actions, and other properties, as follows. At least one match criterion and one action argument should ordinarily be specified.

        idle_timeout=seconds
            These key-value pairs have the same meaning as in the usual ovs-ofctl flow syntax.

        fin_idle_timeout=seconds
            Adds a fin_timeout action with the specified arguments to the new flow. This feature was added in Open vSwitch 1.5.90.

        table=number
            The table in which the new flow should be inserted. Specify a decimal number between 0 and 254. The default, if table is unspecified, is table 1.

        field=value
            Adds a match criterion to the new flow.

            The first form specifies that field must match the literal value, e.g. dl_type=0x0800. All of the fields and values for ovs-ofctl flow syntax are available with their usual meanings.

            The second form specifies that field[start..end] in the new flow must match src[start..end] taken from the flow currently being processed.

            The third form is a shorthand for the second form. It specifies that field[start..end] in the new flow must match field[start..end] taken from the flow currently being processed.

        load:value->dst[start..end]
            Adds a load action to the new flow.

            The first form loads the literal value into bits start through end, inclusive, in field dst. Its syntax is the same as the load action described earlier in this section.

            The second form loads src[start..end], a value from the flow currently being processed, into bits start through end, inclusive, in field dst.

        output:field[start..end]
            Add an output action to the new flow's actions, that outputs to the OpenFlow port taken from field[start..end], which must be an NXM field as described above.

        For best performance, segregate learned flows into a table (using table=number) that is not used for any other flows except possibly for a lowest-priority ``catch-all'' flow, that is, a flow with no match criteria. (This is why the default table is 1, to keep the learned flows separate from the primary flow table 0.)

    apply_actions([action][,action...])
        Applies the specific action(s) immediately. The syntax of actions are same to actions= field.

    clear_actions
        Clears all the actions in the action set immediately.

    write_metadata:value[/mask]
        Updates the metadata field for the flow. If mask is omitted, the metadata field is set exactly to value; if mask is specified, then a 1-bit in mask indicates that the corresponding bit in the metadata field will be replaced with the corresponding bit from value. Both value and mask are 64-bit values that are decimal by default; use a 0x prefix to specify them in hexadecimal.

    goto_table:table
        Indicates the next table in the process pipeline.

    fin_timeout(argument[,argument])
        This action changes the idle timeout or hard timeout, or both, of this OpenFlow rule when the rule matches a TCP packet with the FIN or RST flag. When such a packet is observed, the action reduces the rule's timeouts to those specified on the action. If the rule's existing timeout is already shorter than the one that the action specifies, then that timeout is unaffected.

        argument takes the following forms:

        idle_timeout=seconds
            Causes the flow to expire after the given number of seconds of inactivity.

        hard_timeout=seconds
            Causes the flow to expire after the given number of seconds, regardless of activity. (seconds specifies time since the flow's creation, not since the receipt of the FIN or RST.)

        This action was added in Open vSwitch 1.5.90.

    sample(argument[,argument]...)
        Samples packets and sends one sample for every sampled packet.

        argument takes the following forms:

        probability=packets
            The number of sampled packets out of 65535. Must be greater or equal to 1.

        collector_set_id=id
            The unsigned 32-bit integer identifier of the set of sample collectors to send sampled packets to. Defaults to 0.

        obs_domain_id=id
            When sending samples to IPFIX collectors, the unsigned 32-bit integer Observation Domain ID sent in every IPFIX flow record. Defaults to 0.

        obs_point_id=id
            When sending samples to IPFIX collectors, the unsigned 32-bit integer Observation Point ID sent in every IPFIX flow record. Defaults to 0.

        Refer to ovs-vswitchd.conf.db(8) for more details on configuring sample collector sets.

        This action was added in Open vSwitch 1.10.90.

    exit
        This action causes Open vSwitch to immediately halt execution of further actions. Those actions which have already been executed are unaffected. Any further actions, including those which may be in other tables, or different levels of the resubmit call stack, are ignored.

An opaque identifier called a cookie can be used as a handle to identify a set of flows:

cookie=value
    A cookie can be associated with a flow using the add-flow, add-flows, and mod-flows commands. value can be any 64-bit number and need not be unique among flows. If this field is omitted, a default cookie value of 0 is used.

cookie=value/mask
    When using NXM, the cookie can be used as a handle for querying, modifying, and deleting flows. value and mask may be supplied for the del-flows, mod-flows, dump-flows, and dump-aggregate commands to limit matching cookies. A 1-bit in mask indicates that the corresponding bit in cookie must match exactly, and a 0-bit wildcards that bit. A mask of -1 may be used to exactly match a cookie.

    The mod-flows command can update the cookies of flows that match a cookie by specifying the cookie field twice (once with a mask for matching and once without to indicate the new value):

    ovs-ofctl mod-flows br0 cookie=1,actions=normal
        Change all flows' cookies to 1 and change their actions to normal.

    ovs-ofctl mod-flows br0 cookie=1/-1,cookie=2,actions=normal
        Update cookies with a value of 1 to 2 and change their actions to normal.

    The ability to match on cookies was added in Open vSwitch 1.5.0.

The following additional field sets the priority for flows added by the add-flow and add-flows commands. For mod-flows and del-flows when --strict is specified, priority must match along with the rest of the flow specification. For mod-flows without --strict, priority is only significant if the command creates a new flow, that is, non-strict mod-flows does not match on priority and will not change the priority of existing flows. Other commands do not allow priority to be specified.

priority=value
    The priority at which a wildcarded entry will match in comparison to others. value is a number between 0 and 65535, inclusive. A higher value will match before a lower one. An exact-match entry will always have priority over an entry containing wildcards, so it has an implicit priority value of 65535. When adding a flow, if the field is not specified, the flow's priority will default to 32768.

    OpenFlow leaves behavior undefined when two or more flows with the same priority can match a single packet. Some users expect ``sensible'' behavior, such as more specific flows taking precedence over less specific flows, but OpenFlow does not specify this and Open vSwitch does not implement it. Users should therefore take care to use priorities to ensure the behavior that they expect.

The add-flow, add-flows, and mod-flows commands support the following additional options. These options affect only new flows. Thus, for add-flow and add-flows, these options are always significant, but for mod-flows they are significant only if the command creates a new flow, that is, their values do not update or affect existing flows.

idle_timeout=seconds
    Causes the flow to expire after the given number of seconds of inactivity. A value of 0 (the default) prevents a flow from expiring due to inactivity.

hard_timeout=seconds
    Causes the flow to expire after the given number of seconds, regardless of activity. A value of 0 (the default) gives the flow no hard expiration deadline.

send_flow_rem
    Marks the flow with a flag that causes the switch to generate a ``flow removed'' message and send it to interested controllers when the flow later expires or is removed.

check_overlap
    Forces the switch to check that the flow match does not overlap that of any different flow with the same priority in the same table. (This check is expensive so it is best to avoid it.)

The dump-flows, dump-aggregate, del-flow and del-flows commands support one additional optional field:

out_port=port
    If set, a matching flow must include an output action to port, which must an OpenFlow port number or name (e.g. local).

  Table Entry Output
The dump-tables and dump-aggregate commands print information about the entries in a datapath's tables. Each line of output is a flow entry as described in Flow Syntax, above, plus some additional fields:

duration=secs
    The time, in seconds, that the entry has been in the table. secs includes as much precision as the switch provides, possibly to nanosecond resolution.

n_packets
    The number of packets that have matched the entry.

n_bytes
    The total number of bytes from packets that have matched the entry.

The following additional fields are included only if the switch is Open vSwitch 1.6 or later and the NXM flow format is used to dump the flow (see the description of the --flow-format option below). The values of these additional fields are approximations only and in particular idle_age will sometimes become nonzero even for busy flows.

hard_age=secs
    The integer number of seconds since the flow was added or modified. hard_age is displayed only if it differs from the integer part of duration. (This is separate from duration because mod-flows restarts the hard_timeout timer without zeroing duration.)

idle_age=secs
    The integer number of seconds that have passed without any packets passing through the flow.

OPTIONS

--strict
    Uses strict matching when running flow modification commands.

-F format[,format...]
    ovs-ofctl supports the following individual flow formats, any number of which may be listed as format:

    OpenFlow10-table_id
        This is the standard OpenFlow 1.0 flow format. All OpenFlow switches and all versions of Open vSwitch support this flow format.

    OpenFlow10+table_id
        This is the standard OpenFlow 1.0 flow format plus a Nicira extension that allows ovs-ofctl to specify the flow table in which a particular flow should be placed. Open vSwitch 1.2 and later supports this flow format.

    NXM-table_id (Nicira Extended Match)
        This Nicira extension to OpenFlow is flexible and extensible. It supports all of the Nicira flow extensions, such as tun_id and registers. Open vSwitch 1.1 and later supports this flow format.

    NXM+table_id (Nicira Extended Match)
        This combines Nicira Extended match with the ability to place a flow in a specific table. Open vSwitch 1.2 and later supports this flow format.

    OXM-OpenFlow12
        These are the standard OXM (OpenFlow Extensible Match) flow format in OpenFlow 1.2 and 1.3, respectively.

    ovs-ofctl also supports the following abbreviations for collections of flow formats:

    any Any supported flow format.

    OpenFlow10
        OpenFlow10-table_id or OpenFlow10+table_id.

    NXM NXM-table_id or NXM+table_id.

    OXM OXM-OpenFlow12 or OXM-OpenFlow13.

    For commands that modify the flow table, ovs-ofctl by default negotiates the most widely supported flow format that supports the flows being added. For commands that query the flow table, ovs-ofctl by default uses the most advanced format supported by the switch.

    This option, where format is a comma-separated list of one or more of the formats listed above, limits ovs-ofctl's choice of flow format. If a command cannot work as requested using one of the specified flow formats, ovs-ofctl will report a fatal error.

-P format
    ovs-ofctl supports the following packet_in formats, in order of increasing capability:

    openflow10
        This is the standard OpenFlow 1.0 packet in format. It should be supported by all OpenFlow switches.

    nxm (Nicira Extended Match)
        This packet_in format includes flow metadata encoded using the NXM format.

    Usually, ovs-ofctl prefers the nxm packet_in format, but will allow the switch to choose its default if nxm is unsupported. When format is one of the formats listed in the above table, ovs-ofctl will insist on the selected format. If the switch does not support the requested format, ovs-ofctl will report a fatal error. This option only affects the monitor command.

--timestamp
    Print a timestamp before each received packet. This option only affects the monitor and snoop commands.

-m  Increases the verbosity of OpenFlow messages printed and logged by ovs-ofctl commands. Specify this option more than once to increase verbosity further.

--sort[=field]
    Display output sorted by flow field in ascending (--sort) or descending (--rsort) order, where field is any of the fields that are allowed for matching or priority to sort by priority. When field is omitted, the output is sorted by priority. Specify these options multiple times to sort by multiple fields.

    Any given flow will not necessarily specify a value for a given field. This requires special treatement:

    •   A flow that does not specify any part of a field that is used for sorting is sorted after all the flows that do specify the field. For example, --sort=tcp_src will sort all the flows that specify a TCP source port in ascending order, followed by the flows that do not specify a TCP source port at all.

    •   A flow that only specifies some bits in a field is sorted as if the wildcarded bits were zero. For example, --sort=nw_src would sort a flow that specifies nw_src=192.168.0.0/24 the same as nw_src=192.168.0.0.

    These options currently affect only dump-flows output.

  Public Key Infrastructure Options

RUNTIME MANAGEMENT COMMANDS
ovs-appctl(8) can send commands to a running ovs-ofctl process. The supported commands are listed below.

exit
    Causes ovs-ofctl to gracefully terminate. This command applies only when executing the monitor or snoop commands.

ofctl/set-output-file file
    Causes all subsequent output to go to file instead of stderr. This command applies only when executing the monitor or snoop commands.

ofctl/send ofmsg...
    Sends each ofmsg, specified as a sequence of hex digits that express an OpenFlow message, on the OpenFlow connection. This command is useful only when executing the monitor command.

ofctl/barrier
    Sends an OpenFlow barrier request on the OpenFlow connection and waits for a reply. This command is useful only for the monitor command.

EXAMPLES
The following examples assume that ovs-vswitchd has a bridge named br0 configured.

ovs-ofctl dump-tables br0
    Prints out the switch's table stats. (This is more interesting after some traffic has passed through.)

ovs-ofctl dump-flows br0
    Prints the flow entries in the switch.

SEE ALSO
ovs-appctl(8), ovs-controller(8), ovs-vswitchd(8) ovs-vswitchd.conf.db(8)