|
HTML rendering created 2025-02-02 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|
BRIDGE(8) Linux BRIDGE(8)
bridge - show / manipulate bridge addresses and devices
bridge [ OPTIONS ] OBJECT { COMMAND | help }
OBJECT := { link | fdb | mdb | vlan | vni | monitor }
OPTIONS := { -V[ersion] | -s[tatistics] | -n[etns] name | -b[atch]
filename | -com[pressvlans] | -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 mdb flush dev DEV [ port PORT ] [ vid VID ] [ src_vni
SRC_VNI ] [ proto PROTO ] [ [no]permanent ] [ dst IPADDR ]
[ dst_port DST_PORT ] [ vni VNI ]
bridge mst set dev DEV msti MSTI state STP_STATE
bridge mst [ [ show ] [ dev DEV ] ]
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 ] [
msti MSTI ]
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 ]
-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.
-com, -compressvlans
Show compressed VLAN list. It will show continuous VLANs
with the range instead of separated VLANs. Default is off.
-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.
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.
link objects correspond to the port devices of the bridge.
The corresponding commands set and display port status and bridge
specific attributes.
bridge link set - set bridge specific attributes on a port
dev NAME
interface name of the bridge port
cost COST
the STP path cost of the specified port.
priority PRIO
the STP port priority. The priority value is an unsigned
8-bit quantity (number between 0 and 255). This metric is
used in the designated port an droot port selection
algorithms.
state STATE
the operation state of the port. Except state 0 (disable
STP or BPDU filter feature), this is primarily used by user
space STP/RSTP implementation. One may enter port state
name (case insensitive), or one of the numbers below.
Negative inputs are ignored, and unrecognized names return
an error.
0 - port is in STP DISABLED state. Make this port
completely inactive for STP. This is also called BPDU
filter and could be used to disable STP on an untrusted
port, like a leaf virtual devices.
1 - port is in STP LISTENING state. Only valid if STP is
enabled on the bridge. In this state the port listens for
STP BPDUs and drops all other traffic frames.
2 - port is in STP LEARNING state. Only valid if STP is
enabled on the bridge. In this state the port will accept
traffic only for the purpose of updating MAC address
tables.
3 - port is in STP FORWARDING state. Port is fully active.
4 - port 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, port will only process STP
BPDUs.
guard on or guard off
Controls whether STP BPDUs will be processed by the bridge
port. By default, the flag is turned off allowed BPDU
processing. Turning this flag on will disables the bridge
port if a STP BPDU packet is received.
If running Spanning Tree on bridge, hostile devices on the
network may send BPDU on a port and cause network failure.
Setting guard on will detect and stop this by disabling the
port. The port will be restarted if link is brought down,
or removed and reattached. For example if guard is enable
on eth0:
ip link set dev eth0 down; ip link set dev eth0 up
hairpin on or hairpin off
Controls whether traffic may be send back out of the port
on which it was received. This option is also called
reflective relay mode, and is used to support basic VEPA
(Virtual Ethernet Port Aggregator) capabilities. By
default, this flag is turned off and the bridge will not
forward traffic back out of the receiving port.
fastleave on or fastleave off
This flag allows the bridge to immediately stop multicast
traffic on a port that receives IGMP Leave message. It is
only used with IGMP snooping is enabled on the bridge. By
default the flag is off.
root_block on or root_block off
Controls whether a given port is allowed to become root
port or not. Only used when STP is enabled on the bridge.
By default the flag is off.
This feature is also called root port guard. If BPDU is
received from a leaf (edge) port, it should not be elected
as root port. This could be used if using STP on a bridge
and the downstream bridges are not fully trusted; this
prevents a hostile guest from rerouting traffic.
learning on or learning off
Controls whether a given port will learn MAC addresses from
received traffic or not. If learning if off, the bridge
will end up flooding any traffic for which it has no FDB
entry. By default this flag is on.
learning_sync on or learning_sync off
Controls whether a given port will sync MAC addresses
learned on device port to bridge FDB.
flood on or flood off
Controls whether unicast traffic for which there is no FDB
entry will be flooded towards this given port. By default
this flag is on.
hwmode Some network interface cards support HW bridge
functionality and they may be configured in different
modes. Currently support modes are:
vepa - Data sent between HW ports is sent on the wire to
the external switch.
veb - bridging happens in hardware.
bcast_flood on or bcast_flood off
Controls flooding of broadcast traffic on the given port.
By default this flag is on.
mcast_flood on or mcast_flood off
Controls whether multicast traffic for which there is no
MDB entry will be flooded towards this given port. By
default this flag is on.
mcast_max_groups MAX_GROUPS
Sets the maximum number of MDB entries that can be
registered for a given port. Attempts to register more MDB
entries at the port than this limit allows will be
rejected, whether they are done through netlink (e.g. the
bridge tool), or IGMP or MLD membership reports. Setting a
limit to 0 has the effect of disabling the limit. The
default value is 0. See also the ip link option
mcast_hash_max.
mcast_router MULTICAST_ROUTER
This flag is almost the same as the per-VLAN flag, see
below, except its value can only be set in the range 0-2.
The default is 1 where the bridge figures out automatically
where an IGMP/MLD querier, MRDISC capable device, or PIM
router, is located. Setting this flag to 2 is useful in
cases where the multicast router does not indicate its
presence in any meaningful way (e.g. older versions of
SMCRoute, or mrouted), or when there is a need for
forwarding both known and unknown IP multicast to a
secondary/backup router.
mcast_to_unicast on or mcast_to_unicast off
Controls whether a given port will replicate packets using
unicast instead of multicast. By default this flag is off.
This is done by copying the packet per host and changing
the multicast destination MAC to a unicast one accordingly.
mcast_to_unicast works on top of the multicast snooping
feature of the bridge. Which means unicast copies are only
delivered to hosts which are interested in it and
signalized this via IGMP/MLD reports previously.
This feature is intended for interface types which have a
more reliable and/or efficient way to deliver unicast
packets than broadcast ones (e.g. WiFi).
However, it should only be enabled on interfaces where no
IGMPv2/MLDv1 report suppression takes place. IGMP/MLD
report suppression issue is usually overcome by the network
daemon (supplicant) enabling AP isolation and by that
separating all STAs.
Delivery of STA-to-STA IP multicast is made possible again
by enabling and utilizing the bridge hairpin mode, which
considers the incoming port as a potential outgoing port,
too (see hairpin option). Hairpin mode is performed after
multicast snooping, therefore leading to only deliver
reports to STAs running a multicast router.
neigh_suppress on or neigh_suppress off
Controls whether neigh discovery (arp and nd) proxy and
suppression is enabled on the port. By default this flag is
off.
neigh_vlan_suppress on or neigh_vlan_suppress off
Controls whether per-VLAN neigh discovery (arp and nd)
proxy and suppression is enabled on the port. When on, the
bridge link option neigh_suppress has no effect and the
per-VLAN state is set using the bridge vlan option
neigh_suppress. By default this flag is off.
vlan_tunnel on or vlan_tunnel off
Controls whether vlan to tunnel mapping is enabled on the
port. By default this flag is off.
isolated on or isolated off
Controls whether a given port will be isolated, which means
it will be able to communicate with non-isolated ports
only. By default this flag is off.
locked on or locked off
Controls whether a port is locked or not. When locked, non-
link-local frames received through the port are dropped
unless an FDB entry with the MAC source address points to
the port. The common use case is IEEE 802.1X where hosts
can authenticate themselves by exchanging EAPOL frames with
an authenticator. After authentication is complete, the
user space control plane can install a matching FDB entry
to allow traffic from the host to be forwarded by the
bridge. When learning is enabled on a locked port, the
no_linklocal_learn bridge option needs to be on to prevent
the bridge from learning from received EAPOL frames. By
default this flag is off.
mab on or mab off
Controls whether MAC Authentication Bypass (MAB) is enabled
on the port or not. MAB can only be enabled on a locked
port that has learning enabled. When enabled, FDB entries
are learned from received traffic and have the "locked" FDB
flag set. The flag can only be set by the kernel and it
indicates that the FDB entry cannot be used to authenticate
the corresponding host. User space can decide to
authenticate the host by replacing the FDB entry and
clearing the "locked" FDB flag. Locked FDB entries can roam
to unlocked (authorized) ports in which case the "locked"
flag is cleared. FDB entries cannot roam to locked ports
regardless of MAB being enabled or not. Therefore, locked
FDB entries are only created if an FDB entry with the given
{MAC, VID} does not already exist. This behavior prevents
unauthenticated hosts from disrupting traffic destined to
already authenticated hosts. Locked FDB entries act like
regular dynamic entries with respect to forwarding and
aging. By default this flag is off.
backup_port DEVICE
If the port loses carrier all traffic will be redirected to
the configured backup port
nobackup_port
Removes the currently configured backup port
backup_nhid NHID
The FDB nexthop object ID (see ip-nexthop(8)) to attach to
packets being redirected to a backup port that has VLAN
tunnel mapping enabled (via the vlan_tunnel option).
Setting a value of 0 (default) has the effect of not
attaching any ID.
self link setting is configured on specified physical device
master link setting is configured on the software bridge (default)
-t, -timestamp
display current time when using monitor option.
bridge link show - list ports configuration for all bridges.
This command displays ports configuration and flags for all
bridges by default.
dev DEV
only display the specific bridge port named DEV.
master DEVICE
only display ports of the bridge named DEVICE. This is
similar to "ip link show master <bridge_device>" command.
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.
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 mdb flush - flush multicast group database entries.
This command flushes the matching multicast group database
entries.
dev DEV
the interface where this group address is associated.
port PORT
the target port for the operation. If the bridge device is
specified then only entries pointing to the bridge itself
will be deleted.
vid VID
the VLAN ID for the operation. Match entries only with the
specified VLAN ID.
src_vni SRC_VNI
the source VNI Network Identifier for the operation. Match
entries only with the specified source VNI.
proto PROTO
the routing protocol identifier for the operation. Match
entries only with the specified routing protocol. Can be a
number or a string from the file /etc/iproute2/rt_protos.
[no]permanent
if specified then only permanent entries will be deleted or
respectively if "no" is prepended then only non-permanent
(temp) entries will be deleted.
dst IPADDR
the IP address of the destination VXLAN tunnel endpoint
where the multicast receivers reside. Match entries only
with the specified destination IP.
dst_port DST_PORT
the UDP destination port number to use to connect to the
remote VXLAN tunnel endpoint. Match entries only with the
specified destination port number.
vni VNI
the VXLAN VNI Network Identifier to use to connect to the
remote VXLAN tunnel endpoint. Match entries only with the
specified destination VNI.
In the multiple spanning tree (MST) model, the active paths
through a network can be different for different VLANs. In other
words, a bridge port can simultaneously forward one subset of
VLANs, while blocking another.
Provided that the mst_enable bridge option is enabled, a group of
VLANs can be forwarded along the same spanning tree by associating
them with the same instance (MSTI) using bridge vlan global set.
bridge mst set - set multiple spanning tree state
Set the spanning tree state for DEV, in the multiple spanning tree
instance MSTI, to STP_STATE.
dev DEV
Interface name of the bridge port.
msti MSTI
The multiple spanning tree instance.
state STP_STATE
The spanning tree state, see the state option of bridge
link set for supported states.
bridge mst show - list MST states
List current MST port states in every MSTI.
dev DEV
If specified, only display states of the bridge port with
this interface name.
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.
msti MSTI
associate the VLAN with the specified multiple spanning
tree instance (MSTI).
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.
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
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.
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.
ip(8)
Please direct bugreports and patches to: <netdev@vger.kernel.org>
Original Manpage by Stephen Hemminger
This page is part of the iproute2 (utilities for controlling
TCP/IP networking and traffic) project. Information about the
project can be found at
⟨http://www.linuxfoundation.org/collaborate/workgroups/networking/iproute2⟩.
If you have a bug report for this manual page, send it to
netdev@vger.kernel.org, shemminger@osdl.org. This page was
obtained from the project's upstream Git repository
⟨https://git.kernel.org/pub/scm/network/iproute2/iproute2.git⟩ on
2025-02-02. (At that time, the date of the most recent commit
that was found in the repository was 2025-01-21.) If you discover
any rendering problems in this HTML version of the page, or you
believe there is a better or more up-to-date source for the page,
or you have corrections or improvements to the information in this
COLOPHON (which is not part of the original manual page), send a
mail to man-pages@man7.org
iproute2 1 August 2012 BRIDGE(8)
|
HTML rendering created 2025-02-02 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|