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ovs-ofctl

ovs-ofctl

Section: Open vSwitch Manual (8) Updated: January 2010
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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.  

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:

ssl:ip[:port]
The specified SSL port (default: 6633) on the host at the given ip, which must be expressed as an IP address (not a DNS name). The --private-key, --certificate, and --ca-cert options are mandatory when this form is used.
tcp:ip[:port]
The specified TCP port (default: 6633) on the host at the given ip, which must be expressed as an IP address (not a DNS name).
unix:file
The Unix domain server socket named file.
file
This is short for unix:file, as long as file does not contain a colon.
bridge
This is short for unix:/var/run/openvswitch/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.
status switch [key]
Prints to the console a series of key-value pairs that report the status of switch. If key is specified, only the key-value pairs whose key names begin with key are printed. If key is omitted, all key-value pairs are printed.
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.
mod-port switch netdev action
Modify characteristics of an interface monitored by switch. netdev can be referred to by its OpenFlow assigned port number or the device name, e.g. eth0. The action may be any one of the following:
up
Enables the interface. This is equivalent to ``ifconfig up'' on a Unix system.
down
Disables the interface. This is equivalent to ``ifconfig down'' on a Unix system.
flood
When a flood action is specified, traffic will be sent out this interface. This is the default posture for monitored ports.
noflood
When a flood action is specified, traffic will not be sent out this interface. This is primarily useful to prevent loops when a spanning tree protocol is not in use.
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.
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 descrbed in Table Entry Output.
queue-stats switch [port [queue]]
Prints to the console statistics for the specified queue on port within switch. Either of port or queue or both may be omitted (or equivalently specified as 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.
add-flow switch flow
Add the flow entry as described by flow to the switch's tables. The flow entry is in the format described in Flow Syntax, below.
add-flows switch file
Add flow entries as described in file to switch's tables. Each line in file is a flow entry in the format described in Flow Syntax, below.
mod-flows switch flow
Modify the actions in entries from the switch's tables that match flow. When invoked with the --strict option, wildcards are not treated as active for matching purposes. See Flow Syntax, below, for the syntax of flows.
del-flows switch [flow]
Deletes entries from the switch's tables that match flow. When invoked with the --strict option, wildcards are not treated as active for matching purposes. If flow is omitted and the --strict option is not used, all flows in the switch's tables are removed. See Flow Syntax, below, for the syntax of flows.
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 /var/run/openvswitch/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]
Connects to switch and prints to the console all OpenFlow messages received. Usually, switch should specify a connection named on ovs-openflowd(8)'s -l or --listen command line option.
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.)
This command may be useful for debugging switch or controller implementations.
 

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.
 

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 * or ANY 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_no
Matches physical port port_no. Switch ports are numbered as displayed by ovs-ofctl show.
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

dl_dst=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_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]

nw_dst=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).
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 is wildcarded or set to a value other than 0x0800 or 0x0806, 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. 6 to match TCP packets).
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 dl_type is wildcarded or set to a value other than 0x0800 or 0x0806, the value of nw_proto is ignored (see Flow Syntax above).
nw_tos=tos
Matches IP ToS/DSCP 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.
The value of nw_proto is ignored unless dl_type=0x0800, ip, icmp, tcp, or udp is also specified (see Flow Syntax above).
tp_src=port

tp_dst=port
When dl_type and nw_proto specify TCP or UDP, tp_src and tp_dst match the UDP or TCP 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).
icmp_type=type

icmp_code=code
When dl_type and nw_proto specify ICMP, 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).
tun_id=tunnel-id
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) will have a nonzero tunnel ID.
tun_id requires use of one of two Nicira extensions to OpenFlow:
NXM (Nicira Extended Match)
This extension fully supports tun_id.
Tunnel ID from Cookie
This extension supports tun_id with two caveats: the top 32 bits of the cookie (see below) are used for tunnel-id and thus unavailable for other use, and specifying tun_id on dump-flows or dump-aggregate has no effect.
When tun_id is specified, ovs-ofctl will automatically attempt to negotiate use of one of these extensions. It will use the ``tunnel ID from cookie'' extension if neither caveat applies and NXM otherwise. If the switch does not support the needed extension, then ovs-ofctl will report a fatal error.
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.
Register matches require support for the NXM (Nicira Extended Match) extension to OpenFlow. When a register match 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.

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.
arp
Same as dl_type=0x0806.

The add-flow and add-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 a decimal port number designating the physical port on which to output the packet, or one of the following keywords:
output:port
Outputs the packet on the port specified by port.
enqueue:port:queue
Enqueues the packet on the specified queue within port port. 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:max_len
Sends the packet to the OpenFlow controller as a ``packet in'' message. If max_len is a number, then it specifies the maximum number of bytes that should be sent. If max_len is ALL or omitted, then the entire packet is sent.
local
Outputs the packet on the ``local port,'' which corresponds to the ofn network device (see CONTACTING THE CONTROLLER in ovs-openflowd(8) for information on the ofn network device).
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.
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 source port to port.
mod_tp_dst:port
Sets the TCP or UDP destination port to port.
mod_nw_tos:tos
Sets the IP ToS/DSCP field to tos. Valid values are between 0 and 255, inclusive. Note that the two lower reserved bits are never modified.
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 the OpenFlow flow table with the in_port field replaced by port and executes the actions found, if any, in addition to any other actions in this flow entry. Recursive resubmit actions are ignored.
set_tunnel:id

set_tunnel64: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.
drop_spoofed_arp
Stops processing further actions, if the packet being processed is an Ethernet+IPv4 ARP packet for which the source Ethernet address inside the ARP packet differs from the source Ethernet address in the Ethernet header. This is useful because OpenFlow does not provide a way to match on the Ethernet addresses inside ARP packets, so there is no other way to drop spoofed ARPs other than sending every ARP packet to a controller.
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.
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.
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.
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 register 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.
(The OpenFlow protocol supports other actions that ovs-ofctl does not yet expose to the user.)

The add-flow, add-flows, and mod-flows commands support an additional optional field:

cookie=value
A cookie is an opaque identifier that can be associated with the flow. value can be any 64-bit number and need not be unique among flows.

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. Other commands ignore the priority value.

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.

The add-flow and add-flows commands support additional optional fields:

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.

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.

The dump-flows and dump-aggregate commands support an additional optional field:

table=number
If specified, limits the flows about which statistics are gathered to those in the table with the given number. Tables are numbered as shown by the dump-tables command. If this field is not specified, or if number is given as 255, statistics are gathered about flows from all tables.
 

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 unique flow entry, which begins with some common information:
duration
The number of seconds the entry has been in the table.
table_id
The table that contains the flow. When a packet arrives, the switch begins searching for an entry at the lowest numbered table. Tables are numbered as shown by the dump-tables command.
priority
The priority of the entry in relation to other entries within the same table. A higher value will match before a lower one.
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 rest of the line consists of a description of the flow entry as described in Flow Syntax, above.  

OPTIONS

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

--flow-format=format
ovs-ofctl supports the following flow formats, in order of increasing capability:
openflow10
This is the standard OpenFlow 1.0 flow format. It should be supported by all OpenFlow switches.
tun_id_from_cookie
This Nicira extension to OpenFlow adds minimal and limited support for tun_id, but it does not support any other Nicira flow extensions. (This flow format is deprecated.)
nxm (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.
Usually, ovs-ofctl picks the correct format automatically. For commands that modify the flow table, ovs-ofctl by default uses the most widely supported flow format that supports the flows being added. For commands that query the flow table, ovs-ofctl by default queries and uses the most advanced format supported by the switch.
This option, where format is one of the formats listed in the above table, overrides ovs-ofctl's default choice of flow format. If a command cannot work as requested using the requested flow format, ovs-ofctl will report a fatal error.
-m

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

Public Key Infrastructure Options

-p privkey.pem

--private-key=privkey.pem
Specifies a PEM file containing the private key used as ovs-ofctl's identity for outgoing SSL connections.
-c cert.pem

--certificate=cert.pem
Specifies a PEM file containing a certificate that certifies the private key specified on -p or --private-key to be trustworthy. The certificate must be signed by the certificate authority (CA) that the peer in SSL connections will use to verify it.
-C cacert.pem

--ca-cert=cacert.pem
Specifies a PEM file containing the CA certificate that ovs-ofctl should use to verify certificates presented to it by SSL peers. (This may be the same certificate that SSL peers use to verify the certificate specified on -c or --certificate, or it may be a different one, depending on the PKI design in use.)
-C none

--ca-cert=none
Disables verification of certificates presented by SSL peers. This introduces a security risk, because it means that certificates cannot be verified to be those of known trusted hosts.
-vmodule[:facility[:level]], --verbose=module[:facility[:level]]
Sets the logging level for module in facility to level:
module may be any valid module name (as displayed by the --list action on ovs-appctl(8)), or the special name ANY to set the logging levels for all modules.
facility may be syslog, console, or file to set the levels for logging to the system log, the console, or a file respectively, or ANY to set the logging levels for both facilities. If it is omitted, facility defaults to ANY.
Regardless of the log levels set for file, logging to a file will not take place unless --log-file is also specified (see below).
level must be one of emer, err, warn, info, or dbg, designating the minimum severity of a message for it to be logged. If it is omitted, level defaults to dbg.
-v, --verbose
Sets the maximum logging verbosity level, equivalent to --verbose=ANY:ANY:dbg.
-vPATTERN:facility:pattern, --verbose=PATTERN:facility:pattern
Sets the log pattern for facility to pattern. Refer to ovs-appctl(8) for a description of the valid syntax for pattern.
--log-file[=file]
Enables logging to a file. If file is specified, then it is used as the exact name for the log file. The default log file name used if file is omitted is /var/log/openvswitch/ovs-ofctl.log.
-h, --help
Prints a brief help message to the console.
-V, --version
Prints version information to the console.
 

EXAMPLES

The following examples assume that an OpenFlow switch on the local host has been configured to listen for management connections on a Unix domain socket named /var/run/openvswitch/openflow.sock, e.g. by specifying --listen=punix:/var/run/openvswitch/openflow.sock on the ovs-openflowd(8) command line.
ovs-ofctl dump-tables unix:/var/run/openvswitch/openflow.sock
Prints out the switch's table stats. (This is more interesting after some traffic has passed through.)
ovs-ofctl dump-flows unix:/var/run/openvswitch/openflow.sock
Prints the flow entries in the switch.
 

SEE ALSO

ovs-appctl(8), ovs-controller(8), ovs-vswitchd(8)


 

Index

NAME
SYNOPSIS
DESCRIPTION
OpenFlow Switch Management Commands
OpenFlow Switch and Controller Commands
Flow Syntax
Table Entry Output
OPTIONS
Public Key Infrastructure Options
EXAMPLES
SEE ALSO

This document was created by man2html, using the manual pages.
Time: 22:02:05 GMT, April 16, 2011