bridge - Man Page

show / manipulate bridge addresses and devices

Synopsis

bridge [ Options ] Object { Command | help }

Object := { link | fdb | mdb | vlan | vni | monitor }

Options := { -V[ersion] | -s[tatistics] | -n[etns] name | -b[atch] filename | -c[olor] | -p[retty] | -j[son] | -o[neline] }

bridge link set dev DEV [ cost COST ] [ priority PRIO ] [ state STATE ] [ guard { on | off } ] [ hairpin { on | off } ] [ fastleave { on | off } ] [ root_block { on | off } ] [ learning { on | off } ] [ learning_sync { on | off } ] [ flood { on | off } ] [ hwmode { vepa | veb } ] [ bcast_flood { on | off } ] [ mcast_flood { on | off } ] [ mcast_max_groups MAX_GROUPS ] [ mcast_router MULTICAST_ROUTER ] [ mcast_to_unicast { on | off } ] [ neigh_suppress { on | off } ] [ neigh_vlan_suppress { on | off } ] [ vlan_tunnel { on | off } ] [ isolated { on | off } ] [ locked { on | off } ] [ mab { on | off } ] [ backup_port DEVICE ] [ nobackup_port ] [ backup_nhid NHID ] [ self ] [ master ]

bridge link [ show ] [ dev DEV ] [ master DEVICE ]

bridge fdb { add | append | del | replace } LLADDR dev DEV { local | static | dynamic } [ self ] [ master ] [ router ] [ use ] [ extern_learn ] [ sticky ] [ src_vni VNI ] { [ dst IPADDR ] [ vni VNI ] [ port PORT ] [ via DEVICE ] | nhid NHID }

bridge fdb [ [ show ] [ br BRDEV ] [ brport DEV ] [ vlan VID ] [ state STATE ] [ dynamic ] ]

bridge fdb get [ to ] LLADDR [ br BRDEV ] { brport | dev } DEV [ vlan VID ] [ vni VNI ] [ self ] [ master ] [ dynamic ]

bridge fdb flush dev DEV [ brport DEV ] [ vlan VID ] [ src_vni VNI ] [ nhid NHID ] [ vni VNI ] [ port PORT ] [ dst IPADDR ] [ self ] [ master ] [ [no]permanent | [no]static | [no]dynamic ] [ [no]added_by_user ] [ [no]extern_learn ] [ [no]sticky ] [ [no]offloaded ] [ [no]router ]

bridge mdb { add | del | replace } dev DEV port PORT grp GROUP [ src SOURCE ] [ permanent | temp ] [ vid VID ] [ filter_mode { include | exclude } ] [ source_list SOURCE_LIST ] [ proto PROTO ] [ dst IPADDR ] [ dst_port DST_PORT ] [ vni VNI ] [ src_vni SRC_VNI ] [ via DEV ]

bridge mdb show [ dev DEV ]

bridge mdb get dev DEV grp GROUP [ src SOURCE ] [ vid VID ] [ src_vni SRC_VNI ]

bridge vlan { add | del } dev DEV vid VID [ tunnel_info TUNNEL_ID ] [ pvid ] [ untagged ] [ self ] [ master ]

bridge vlan set dev DEV vid VID [ state STP_STATE ] [ mcast_max_groups MAX_GROUPS ] [ mcast_router MULTICAST_ROUTER ] [ neigh_suppress { on | off } ]

bridge vlan [ show | tunnelshow ] [ dev DEV ]

bridge vlan global set dev DEV vid VID [ mcast_snooping MULTICAST_SNOOPING ] [ mcast_querier MULTICAST_QUERIER ] [ mcast_igmp_version IGMP_VERSION ] [ mcast_mld_version MLD_VERSION ] [ mcast_last_member_count LAST_MEMBER_COUNT ] [ mcast_last_member_interval LAST_MEMBER_INTERVAL ] [ mcast_startup_query_count STARTUP_QUERY_COUNT ] [ mcast_startup_query_interval STARTUP_QUERY_INTERVAL ] [ mcast_membership_interval MEMBERSHIP_INTERVAL ] [ mcast_querier_interval QUERIER_INTERVAL ] [ mcast_query_interval QUERY_INTERVAL ] [ mcast_query_response_interval QUERY_RESPONSE_INTERVAL ]

bridge vlan global [ show ] [ dev DEV ] [ vid VID ]

bridge vlan show [ dev DEV ]

bridge vni { add | del } dev DEV vni VNI [ { group | remote } IPADDR ]

bridge vni show [ dev DEV ]

bridge monitor [ all | neigh | link | mdb | vlan ]

Options

-V,  -Version

print the version of the bridge utility and exit.

-s,  -stats,  -statistics

output more information. If this option is given multiple times, the amount of information increases. As a rule, the information is statistics or some time values.

-d,  -details

print detailed information about bridge vlan filter entries or MDB router ports.

-n,  -net,  -netns <NETNS>

switches bridge to the specified network namespace NETNS. Actually it just simplifies executing of:

ip netns exec NETNS bridge [ OPTIONS ] Object { Command | help }

to

bridge -n[etns] NETNS [ OPTIONS ] Object { Command | help }

-b,  -batch <FILENAME>

Read commands from provided file or standard input and invoke them. First failure will cause termination of bridge command.

-force

Don't terminate bridge command on errors in batch mode. If there were any errors during execution of the commands, the application return code will be non zero.

-c[color][={always|auto|never}

Configure color output. If parameter is omitted or always, color output is enabled regardless of stdout state. If parameter is auto, stdout is checked to be a terminal before enabling color output. If parameter is never, color output is disabled. If specified multiple times, the last one takes precedence. This flag is ignored if -json is also given.

-j,  -json

Output results in JavaScript Object Notation (JSON).

-p,  -pretty

When combined with -j generate a pretty JSON output.

-o,  -oneline

output each record on a single line, replacing line feeds with the '\' character. This is convenient when you want to count records with wc(1) or to grep(1) the output.

Bridge - Command Syntax

Object

link

- Bridge port.

fdb

- Forwarding Database entry.

mdb

- Multicast group database entry.

vlan

- VLAN filter list.

vni

- VNI filter list.

Command

Specifies the action to perform on the object. The set of possible actions depends on the object type. As a rule, it is possible to add, delete and show (or list ) objects, but some objects do not allow all of these operations or have some additional commands. The help command is available for all objects. It prints out a list of available commands and argument syntax conventions.

If no command is given, some default command is assumed. Usually it is list or, if the objects of this class cannot be listed, help.

bridge fdb - forwarding database management

fdb objects contain known Ethernet addresses on a link.

The corresponding commands display fdb entries, add new entries, append entries, and delete old ones.

bridge fdb add - add a new fdb entry

This command creates a new fdb entry.

LLADDR

the Ethernet MAC address.

dev DEV

the interface to which this address is associated.

local - is a local permanent fdb entry, which means that the bridge will not forward frames with this destination MAC address and VLAN ID, but terminate them locally. This flag is default unless "static" or "dynamic" are explicitly specified.

permanent - this is a synonym for "local"

static - is a static (no arp) fdb entry

dynamic - is a dynamic reachable age-able fdb entry

self - the operation is fulfilled directly by the driver for the specified network device. If the network device belongs to a master like a bridge, then the bridge is bypassed and not notified of this operation (and if the device does notify the bridge, it is driver-specific behavior and not mandated by this flag, check the driver for more details). The "bridge fdb add" command can also be used on the bridge device itself, and in this case, the added fdb entries will be locally terminated (not forwarded). In the latter case, the "self" flag is mandatory. The flag is set by default if "master" is not specified.

master - if the specified network device is a port that belongs to a master device such as a bridge, the operation is fulfilled by the master device's driver, which may in turn notify the port driver too of the address. If the specified device is a master itself, such as a bridge, this flag is invalid.

router - the destination address is associated with a router. Valid if the referenced device is a VXLAN type device and has route short circuit enabled.

use - the address is in use. User space can use this option to indicate to the kernel that the fdb entry is in use.

extern_learn - this entry was learned externally. This option can be used to indicate to the kernel that an entry was hardware or user-space controller learnt dynamic entry. Kernel will not age such an entry.

sticky - this entry will not change its port due to learning.

The next command line parameters apply only when the specified device DEV is of type VXLAN.

dst IPADDR

the IP address of the destination VXLAN tunnel endpoint where the Ethernet MAC ADDRESS resides.

src_vni VNI

the src VNI Network Identifier (or VXLAN Segment ID) this entry belongs to. Used only when the vxlan device is in external or collect metadata mode. If omitted the value specified at vxlan device creation will be used.

vni VNI

the VXLAN VNI Network Identifier (or VXLAN Segment ID) to use to connect to the remote VXLAN tunnel endpoint. If omitted the value specified at vxlan device creation will be used.

port PORT

the UDP destination PORT number to use to connect to the remote VXLAN tunnel endpoint. If omitted the default value is used.

via DEVICE

device name of the outgoing interface for the VXLAN device driver to reach the remote VXLAN tunnel endpoint.

nhid NHID

ecmp nexthop group for the VXLAN device driver to reach remote VXLAN tunnel endpoints.

bridge fdb append - append a forwarding database entry

This command adds a new fdb entry with an already known LLADDR. Valid only for multicast link layer addresses. The command adds support for broadcast and multicast Ethernet MAC addresses. The Ethernet MAC address is added multiple times into the forwarding database and the vxlan device driver sends a copy of the data packet to each entry found.

The arguments are the same as with bridge fdb add.

bridge fdb delete - delete a forwarding database entry

This command removes an existing fdb entry.

The arguments are the same as with bridge fdb add.

bridge fdb replace - replace a forwarding database entry

If no matching entry is found, a new one will be created instead.

The arguments are the same as with bridge fdb add.

bridge fdb show - list forwarding entries.

This command displays the current forwarding table.

With the -statistics option, the command becomes verbose. It prints out the last updated and last used time for each entry.

bridge fdb get - get bridge forwarding entry.

lookup a bridge forwarding table entry.

LLADDR

the Ethernet MAC address.

dev DEV

the interface to which this address is associated.

brport DEV

the bridge port to which this address is associated. same as dev above.

br DEV

the bridge to which this address is associated.

self

- the address is associated with the port drivers fdb. Usually hardware.

master

- the address is associated with master devices fdb. Usually software (default).

bridge fdb flush - flush bridge forwarding table entries.

flush the matching bridge forwarding table entries. Some options below have a negated form when "no" is prepended to them (e.g. permanent and nopermanent).

dev DEV

the target device for the operation. If the device is a bridge port and "master" is set then the operation will be fulfilled by its master device's driver and all entries pointing to that port will be deleted.

brport DEV

the target bridge port for the operation. If the bridge device is specified then only entries pointing to the bridge itself will be deleted. Note that the target device specified by this option will override the one specified by dev above.

vlan VID

the target VLAN ID for the operation. Match forwarding table entries only with the specified VLAN ID.

src_vni VNI

the src VNI Network Identifier (or VXLAN Segment ID) for the operation. Match forwarding table entries only with the specified VNI. Valid if the referenced device is a VXLAN type device.

nhid NHID

the ECMP nexthop group for the operation. Match forwarding table entries only with the specified NHID. Valid if the referenced device is a VXLAN type device.

vni VNI

the VXLAN VNI Network Identifier (or VXLAN Segment ID) for the operation. Match forwarding table entries only with the specified VNI. Valid if the referenced device is a VXLAN type device.

port PORT

the UDP destination PORT number for the operation. Match forwarding table entries only with the specified PORT. Valid if the referenced device is a VXLAN type device.

dst IPADDR

the IP address of the destination VXLAN tunnel endpoint for the operation. Match forwarding table entries only with the specified IPADDR. Valid if the referenced device is a VXLAN type device.

self

the operation is fulfilled directly by the driver for the specified network device. If the network device belongs to a master like a bridge, then the bridge is bypassed and not notified of this operation. The "bridge fdb flush" command can also be used on the bridge device itself. The flag is set by default if "master" is not specified.

master

if the specified network device is a port that belongs to a master device such as a bridge, the operation is fulfilled by the master device's driver. Flush with both 'master' and 'self' is not recommended with attributes that are not supported by all devices (e.g., vlan, vni). Such command will be handled by bridge or VXLAN driver, but will return an error from the driver that does not support the attribute. Instead, run flush twice - once with 'self' and once with 'master', and each one with the supported attributes.

[no]permanent

if specified then only permanent entries will be deleted or respectively if "no" is prepended then only non-permanent entries will be deleted.

[no]static

if specified then only static entries will be deleted or respectively if "no" is prepended then only non-static entries will be deleted.

[no]dynamic

if specified then only dynamic entries will be deleted or respectively if "no" is prepended then only non-dynamic (static or permanent) entries will be deleted.

[no]added_by_user

if specified then only entries with added_by_user flag will be deleted or respectively if "no" is prepended then only entries without added_by_user flag will be deleted.

[no]extern_learn

if specified then only entries with extern_learn flag will be deleted or respectively if "no" is prepended then only entries without extern_learn flag will be deleted.

[no]sticky

if specified then only entries with sticky flag will be deleted or respectively if "no" is prepended then only entries without sticky flag will be deleted.

[no]offloaded

if specified then only entries with offloaded flag will be deleted or respectively if "no" is prepended then only entries without offloaded flag will be deleted.

[no]router

if specified then only entries with router flag will be deleted or respectively if "no" is prepended then only entries without router flag will be deleted. Valid if the referenced device is a VXLAN type device.

bridge mdb - multicast group database management

mdb objects contain known IP or L2 multicast group addresses on a link.

The corresponding commands display mdb entries, add new entries, replace entries and delete old ones.

bridge mdb add - add a new multicast group database entry

This command creates a new mdb entry.

dev DEV

the interface where this group address is associated.

port PORT

the port whose link is known to have members of this multicast group.

grp GROUP

the multicast group address (IPv4, IPv6 or L2 multicast) whose members reside on the link connected to the port.

permanent - the mdb entry is permanent. Optional for IPv4 and IPv6, mandatory for L2.

temp - the mdb entry is temporary (default)

src SOURCE

optional source IP address of a sender for this multicast group. If IGMPv3 for IPv4, or MLDv2 for IPv6 respectively, are enabled it will be included in the lookup when forwarding multicast traffic.

vid VID

the VLAN ID which is known to have members of this multicast group.

filter_mode include or filter_mode exclude

controls whether the sources in the entry's source list are in INCLUDE or EXCLUDE mode. Can only be set for (*, G) entries.

source_list SOURCE_LIST

optional list of source IP addresses of senders for this multicast group, separated by a ','.  Whether the entry forwards packets from these senders or not is determined by the entry's filter mode, which becomes a mandatory argument. Can only be set for (*, G) entries.

proto PROTO

the routing protocol identifier of this mdb entry. Can be a number or a string from the file /etc/iproute2/rt_protos. If the routing protocol is not given, then static is assumed.

The next command line parameters apply only when the specified device DEV is of type VXLAN.

dst IPADDR

the IP address of the destination VXLAN tunnel endpoint where the multicast receivers reside.

dst_port DST_PORT

the UDP destination port number to use to connect to the remote VXLAN tunnel endpoint. If omitted, the value specified at VXLAN device creation will be used.

vni VNI

the VXLAN VNI Network Identifier to use to connect to the remote VXLAN tunnel endpoint. If omitted, the value specified at VXLAN device creation will be used or the source VNI when the VXLAN device is in external mode.

src_vni SRC_VNI

the source VNI Network Identifier this entry belongs to. Used only when the VXLAN device is in external mode. If omitted, the value specified at VXLAN device creation will be used.

via DEV

device name of the outgoing interface for the VXLAN device to reach the remote VXLAN tunnel endpoint.

The 0.0.0.0 and :: MDB entries are special catchall entries used to flood IPv4 and IPv6 unregistered multicast packets, respectively. Therefore, when these entries are programmed, the catchall 00:00:00:00:00:00 FDB entry will only flood broadcast, unknown unicast and link-local multicast.

bridge mdb delete - delete a multicast group database entry

This command removes an existing mdb entry.

The arguments are the same as with bridge mdb add.

bridge mdb replace - replace a multicast group database entry

If no matching entry is found, a new one will be created instead.

The arguments are the same as with bridge mdb add.

bridge mdb show - list multicast group database entries

This command displays the current multicast group membership table. The table is populated by IGMP and MLD snooping in the bridge driver automatically. It can be altered by bridge mdb add and bridge mdb del commands manually too.

dev DEV

the interface only whose entries should be listed. Default is to list all bridge interfaces.

With the -details option, the command becomes verbose. It prints out the ports known to have a connected router.

With the -statistics option, the command displays timer values for mdb and router port entries.

bridge mdb get - get multicast group database entry.

This command retrieves a multicast group database entry based on its key.

dev DEV

the interface where this group address is associated.

grp GROUP

the multicast group address (IPv4, IPv6 or L2 multicast).

src SOURCE

the source IP address. Only relevant when retrieving an (S, G) entry.

vid VID

the VLAN ID. Only relevant when the bridge is VLAN-aware.

src_vni SRC_VNI

the source VNI Network Identifier. Only relevant when the VXLAN device is in external mode.

bridge vlan - VLAN filter list

vlan objects contain known VLAN IDs for a link.

The corresponding commands display vlan filter entries, add new entries, and delete old ones.

bridge vlan add - add a new vlan filter entry

This command creates a new vlan filter entry.

dev NAME

the interface with which this vlan is associated.

vid VID

the VLAN ID that identifies the vlan.

tunnel_info TUNNEL_ID

the TUNNEL ID that maps to this vlan. The tunnel id is set in dst_metadata for every packet that belongs to this vlan (applicable to bridge ports with vlan_tunnel flag set).

pvid

the vlan specified is to be considered a PVID at ingress. Any untagged frames will be assigned to this VLAN.

untagged

the vlan specified is to be treated as untagged on egress.

self

the vlan is configured on the specified physical device. Required if the device is the bridge device.

master

the vlan is configured on the software bridge (default).

bridge vlan delete - delete a vlan filter entry

This command removes an existing vlan filter entry.

The arguments are the same as with bridge vlan add. The pvid and untagged flags are ignored.

bridge vlan set - change vlan filter entry's options

This command changes vlan filter entry's options.

dev NAME

the interface with which this vlan is associated.

vid VID

the VLAN ID that identifies the vlan.

state STP_STATE

the operation state of the vlan. One may enter STP state name (case insensitive), or one of the numbers below. Negative inputs are ignored, and unrecognized names return an error. Note that the state is set only for the vlan of the specified device, e.g. if it is a bridge port then the state will be set only for the vlan of the port.

0 - vlan is in STP DISABLED state. Make this vlan completely inactive for STP. This is also called BPDU filter and could be used to disable STP on an untrusted vlan.

1 - vlan is in STP LISTENING state. Only valid if STP is enabled on the bridge. In this state the vlan listens for STP BPDUs and drops all other traffic frames.

2 - vlan is in STP LEARNING state. Only valid if STP is enabled on the bridge. In this state the vlan will accept traffic only for the purpose of updating MAC address tables.

3 - vlan is in STP FORWARDING state. This is the default vlan state.

4 - vlan is in STP BLOCKING state. Only valid if STP is enabled on the bridge. This state is used during the STP election process. In this state, the vlan will only process STP BPDUs.

mcast_max_groups MAX_GROUPS

Sets the maximum number of MDB entries that can be registered for a given VLAN on a given port. A VLAN-specific equivalent of the per-port option of the same name, see above for details.

Note that this option is only available when ip link option mcast_vlan_snooping is enabled.

mcast_router MULTICAST_ROUTER

configure this vlan and interface's multicast router mode, note that only modes 0 - 2 are available for bridge devices. A vlan and interface with a multicast router will receive all multicast traffic. MULTICAST_ROUTER may be either

0 - to disable multicast router.

1 - to let the system detect the presence of routers (default).

2 - to permanently enable multicast traffic forwarding on this vlan and interface.

3 - to temporarily mark this vlan and port as having a multicast router, i.e. enable multicast traffic forwarding. This mode is available only for ports.

neigh_suppress on or neigh_suppress off

Controls whether neigh discovery (arp and nd) proxy and suppression is enabled for a given VLAN on a given port. By default this flag is off.

Note that this option only takes effect when bridge link option neigh_vlan_suppress is enabled for a given port.

bridge vlan show - list vlan configuration.

This command displays the current VLAN filter table.

With the -details option, the command becomes verbose. It displays the per-vlan options.

With the -statistics option, the command displays per-vlan traffic statistics.

bridge vlan tunnelshow - list vlan tunnel mapping.

This command displays the current vlan tunnel info mapping.

bridge vlan global set - change vlan filter entry's global options

This command changes vlan filter entry's global options.

dev NAME

the interface with which this vlan is associated. Only bridge devices are supported for global options.

vid VID

the VLAN ID that identifies the vlan.

mcast_snooping MULTICAST_SNOOPING

turn multicast snooping for VLAN entry with VLAN ID on (MULTICAST_SNOOPING > 0) or off (MULTICAST_SNOOPING == 0). Default is on.

mcast_querier MULTICAST_QUERIER

enable (MULTICAST_QUERIER > 0) or disable (MULTICAST_QUERIER == 0) IGMP/MLD querier, ie sending of multicast queries by the bridge. Default is disabled.

mcast_igmp_version IGMP_VERSION

set the IGMP version. Default is 2.

mcast_mld_version MLD_VERSION

set the MLD version. Default is 1.

mcast_last_member_count LAST_MEMBER_COUNT

set multicast last member count, ie the number of queries the bridge will send before stopping forwarding a multicast group after a "leave" message has been received. Default is 2.

mcast_last_member_interval LAST_MEMBER_INTERVAL

interval between queries to find remaining members of a group, after a "leave" message is received.

mcast_startup_query_count STARTUP_QUERY_COUNT

set the number of queries to send during startup phase. Default is 2.

mcast_startup_query_interval STARTUP_QUERY_INTERVAL

interval between queries in the startup phase.

mcast_membership_interval MEMBERSHIP_INTERVAL

delay after which the bridge will leave a group, if no membership reports for this group are received.

mcast_querier_interval QUERIER_INTERVAL

interval between queries sent by other routers. If no queries are seen after this delay has passed, the bridge will start to send its own queries (as if mcast_querier was enabled).

mcast_query_interval QUERY_INTERVAL

interval between queries sent by the bridge after the end of the startup phase.

mcast_query_response_interval QUERY_RESPONSE_INTERVAL

set the Max Response Time/Maximum Response Delay for IGMP/MLD queries sent by the bridge.

bridge vlan global show - list global vlan options.

This command displays the global VLAN options for each VLAN entry.

dev DEV

the interface only whose VLAN global options should be listed. Default is to list all bridge interfaces.

vid VID

the VLAN ID only whose global options should be listed. Default is to list all vlans.

bridge vni - VNI filter list

vni objects contain known VNI IDs for a dst metadata vxlan link.

The corresponding commands display vni filter entries, add new entries, and delete old ones.

bridge vni add - add a new vni filter entry

This command creates a new vni filter entry.

dev NAME

the interface with which this vni is associated.

vni VNI

the VNI ID that identifies the vni.

remote IPADDR

specifies the unicast destination IP address to use in outgoing packets when the destination link layer address is not known in the VXLAN device forwarding database. This parameter cannot be specified with the group.

group IPADDR

specifies the multicast IP address to join for this VNI

bridge vni del - delete a new vni filter entry

This command removes an existing vni filter entry.

The arguments are the same as with bridge vni add.

bridge vni show - list vni filtering configuration.

This command displays the current vni filter table.

With the -statistics option, the command displays per-vni traffic statistics.

dev NAME

shows vni filtering table associated with the vxlan device

bridge monitor - state monitoring

The bridge utility can monitor the state of devices and addresses continuously. This option has a slightly different format. Namely, the monitor command is the first in the command line and then the object list follows:

bridge monitor [ all | OBJECT-LIST ]

OBJECT-LIST is the list of object types that we want to monitor. It may contain link, fdb, vlan and mdb. If no file argument is given, bridge opens RTNETLINK, listens on it and dumps state changes in the format described in previous sections.

If a file name is given, it does not listen on RTNETLINK, but opens the file containing RTNETLINK messages saved in binary format and dumps them.

Notes

This command uses facilities added in Linux 3.0.

Although the forwarding table is maintained on a per-bridge device basis the bridge device is not part of the syntax. This is a limitation of the underlying netlink neighbour message protocol. When displaying the forwarding table, entries for all bridges are displayed. Add/delete/modify commands determine the underlying bridge device based on the bridge to which the corresponding ethernet device is attached.

See Also

ip(8)

Bugs

Please direct bugreports and patches to: <netdev@vger.kernel.org>

Author

Original Manpage by Stephen Hemminger

Referenced By

batctl(8).

1 August 2012 iproute2 Linux