bgp

For BGP-related configuration, use the command bgp in BGP Router Configuration Mode. For options, see the Parameters section below.

bgp

bgp
{ {always-compare-med }
{ | asnotation } { dot }
{ | bestpath } { med } { dot }
{ | client-to-client } { reflection }
{ | cluster-id } { <cluster id value> } { <ip_addr(A.B.C.D)> }
{ | comm-filter } { <comm-value(4294967041-4294967043,65536-4294901759)> } { <permit } { | deny> } { <in } { | out> }
{ | comm-policy } { <ip-address> } { <prefixlen> } { <set-add } { | set-none } { | modify> }
{ | comm-route } { {additive } { | delete} } { <ip-address> } { <prefixlen> } { comm-value } { <4294967041-4294967043,65536-4294901759> }
{ | confederation } { {identifier } { <AS no> } { | peers } { <AS no>} }
{ | dampening } { <HalfLife-Time(600-2700)> } { <Reuse-Value(100-10800)> } { <Suppress-Value(2000-3999)> } { <Max-Suppress-Time(1800-10800)> }
{ | default } { {ipv4-unicast } { | local-preference } { <Local Pref Value (0-2147483647)>} }
{ | ecomm-filter } { <ecomm-value(xx:xx:xx:xx:xx:xx:xx:xx)> } { <permit } { | deny> } { <in } { | out> }
{ | ecomm-policy } { <ip-address> } { <prefixlen> } { <set-add } { | set-none } { | modify> }
{ | ecomm-route } { {additive } { | delete} } { <ip-address> } { <prefixlen> } { ecomm-value } { <value(xx:xx:xx:xx:xx:xx:xx:xx)> }
{ | graceful-restart } { [restart-time } { <(1-4096)<seconds>] } { [stalepath-time } { <(90-3600)<seconds>] }
{ | local-preference } { <1-100> } { remote-as } { <AS no> } { <ip-address } { | ip6-address> } { <prefixlen> } { [intermediate-as } { <AS-no list- AS1,AS2,...AS10>] } { value } { <value> } { direction } { {in } { | out} } { [override] }
{ | med } { <1-100> } { remote-as } { <AS no> } { <ip-address> } { <prefixlen> } { [intermediate-as } { <AS-no list- AS1,AS2,...AS10>] } { value } { <value> } { direction } { {in } { | out} } { [override] }
{ | nonbgproute-advt } { <external } { |both> }
{ | redistribute-internal }
{ | router-id } { A.B.C.D(<ucast_addr>) }
{ | trap } { <external } { |both> }
{ | update-delay } { <(60-1800)seconds> }
{ | update-filter } { <1-100> } { <permit } { | deny> } { remote-as } { <AS no> } { <ip-address> } { <prefixlen> } { [intermediate-as } { <AS-no list- AS1,AS2,...AS10>] } { direction } { {in } { | out} }

no bgp

no bgp
{ {always-compare-med }
{ | asnotation } { dot }
{ | client-to-client } { reflection } { | cluster-id } { <cluster id value> } { <ip_addr(A.B.C.D)> }
{ | comm-filter } { <comm-value(4294967041-4294967043,65536-4294901759)> } { <permit } { | deny> } { <in } { | out> }
{ | comm-policy } { <ip-address> } { <prefixlen> }
{ | comm-route } { {additive } { | delete} } { <ip-address> } { <prefixlen> } { comm-value } { <4294967041-4294967043,65536-4294901759> }
{ | confederation } { {identifier } { | peers } { <AS no>} }
{ | dampening }
{ | default } { {ipv4-unicast } { | local-preference }
{ | ecomm-filter } { <ecomm-value(xx:xx:xx:xx:xx:xx:xx:xx)> } { <permit } { | deny> } { <in } { | out> }
{ | ecomm-policy } { <ip-address> } { <prefixlen> } { | ecomm-route }
{ | graceful-restart } { [restart-time] } { [stalepath-time] }
{ | local-preference } { <1-100> } { | med } { <1-100> } { | nonbgproute-advt }
{ | redistribute-internal } { | router-id } { | update-delay }
{ | update-filter } { <1-100> }

Parameters

Parameter Type Description
always-compare-med   Enter to enable the comparison of Multi Exit Discriminator (MED) for routes received from different AS. The MED is one of the parameters that is considered when selecting the best path among many alternative paths. The path with a lower MED is preferred over a path with a higher MED. The no form of the command disables the comparison of MED for routes received from different autonomous system. MED will be compared only for routes from same neighbor autonomous system
asnotation dot   Enter to change the output format of BGP ASNs (Autonomous System numbers) from asplain to asdot notation. The no form of the command resets the output format of BGP ASNs from asdot to asplain notation. By default, the output format of BGP ASNs is asplain. Note that BGP asnotation can be changed only if four-byte-ASN is enabled.
bestpath med confed   Enter to enable Multi Exit Discriminator (MED) comparison among paths learnt from confederation peers. The comparison between MEDs is only made if there are no external autonomous systems in the path. If there is an external autonomous system in the path, then the external MED is passed transparently through the confederation, and the comparison is not made. The no form of the command disables MED comparison among paths learnt from confed peers and prevent the software from considering the MED attribute in comparing paths. As default, in BGP route selection algorithm, MED attributes comparison between two routes originated within the local confederation is disabled.
client-to-client reflection   Enter to configure the Route Reflector to support route reflection to Client Peers. By default, the clients of a route reflector are not required to be fully meshed and the routes from a client are reflected to other clients. If the clients are fully meshed, route reflection is not required. The no form of the command disables client-to-client reflection. If disabled, then Route Reflector will not advertise routes learnt from a client peer to other client peers. This occurs when all peers within a cluster are fully-meshed and the client peer itself is able to advertise routes to other clients of the route-reflector
cluster-id   Enter to configure the Cluster ID for the Router Reflector of the BGP cluster which has more than one route reflector. Usually in a cluster of clients with single route reflector the cluster is identified by the router ID of the route reflector. In order to increase redundancy and avoid a single point of failure, a cluster might have more than one route reflector. In this case, all route reflectors in the cluster must be configured with the 4-byte cluster ID so that a route reflector can recognize updates from route reflectors in the same cluster. The no form of the command resets the Cluster ID for the Route Reflector.
cluster id value   Enter a value for the Cluster ID. It ranges from 1 to 4294967295.
ip_address/integer   Enter a value for the Cluster ID.
comm-filter   Enter to allow/ filter the community attribute while receiving or advertising. The rules to filter out the updates are based on the AS from which it is received, NLRI and AS through which it had passed. The no form of the command removes the filter policy for the community attribute.
comm-value(4294967041-4294967043,65536-4294901759   Enter to configure the community attribute value.
deny   Enter to filter routes containing the community attribute value in received or advertised updates.
permit   Enter to allow a particular community attribute to be received or advertised in updates. This is the default option.
in   Enter to configure the direction of route-updates on which the community filter policy needs to be applied as in. This indicates that the community filter needs to be applied on received routes.
out   Enter to configure the direction of route-updates on which the community filter policy needs to be applied as out. This indicates that the community filter needs to be applied on routes advertised to peers.
comm-policy   Enter to configure the community attribute advertisement policy for specific destination. The no form of the command removes the community attribute advertisement policy for specific destination.
<ip-address>   Enter to configure the route prefix on which community policy needs to be applied.
<prefixlen>   Enter to configure the IP prefix length for the destination. These bits are common among all hosts within a network. This value ranges from 1 to 32.
set-add   Enter to send only the configured additive communities with associated route.
set-none   Enter to send the associated route without any communities.
modify   Enter to remove the associated route with received delete communities and to add the configured additive communities.
comm-route   Enter to configure an entry in additive or delete community table for a given destination. The no form of the command removes the entry from additive or delete community table
additive   Enter to add an associated community value with the already existing communities in the route update.
delete   Enter to remove the community attribute from the route-prefix when it passes through the filter process.
<ip-address>   Enter to configure the Route prefix on which community policy needs to be applied.
<prefixlen>   Enter to configure the IP prefix length for the destination. These bits are common among all hosts within a network. This value ranges from 1 to 32.
comm-value <4294967041-4294967043,65536-4294901759>   Enter to configure the community attribute value. This value ranges from 4294967041 to 4294967043 or from 65536 to 4294901759.
confederation   Enter to configure the BGP confederation to which the AS belong to.
identifier <AS no>   Enter to configure the BGP confederation identifier for the confederation to which the autonomous systems belong to. This value ranges from 1 to 4294967295 or 0.1 to 65535.65535. The no form of the command removes the configured BGP confederation identifier and resets the identifier to its default value.
Note:

If this value is already configured to a non-zero value, it must be reset to zero (using no form of the command) before reconfiguring.

Note:

When four-bit-asn is enabled, This value ranges from 1 to 4294967295or between 0.1 and 65535.65535.

Note:

When four-bit-asn is disabled, This value ranges from 1 to 65535. or between 0.1 and 0.65535

Note:

When bgp asnotation is enabled, the AS number of the BGP Speaker is displayed in the range 0.1 to 65535.65535
peers <AS no>   Enter to configure the ASs that are visible internally to a confederation. Each autonomous system is fully meshed within itself. This value ranges from 1 to 4294967295 or 0.1 to 65535.65535. By default, no AS will be added to the confederation. The no form of the command removes the Autonomous Systems from the confederation.
Note:

When four-bit-asn is enabled, This value ranges from 1 to 4294967295or between 0.1 and 65535.65535.

Note:

When four-bit-asn is disabled, This value ranges from 1 to 65535. or between 0.1 and 0.65535

Note:

When bgp asnotation is enabled, the AS number of the BGP Speaker is displayed in the range 0.1 to 65535.65535
dampening   Enter to enable the BGP dampening parameters. The no form of the command disables the BGP dampening feature but does not reset the other configured RFD parameters
<HalfLife-Time (600-2700)>   Enter to configure the time (in seconds) after which a penalty is decreased by half. Once a route has been assigned a penalty, the penalty is decreased for every 5 seconds. BGP’s route flap damping algorithm calculates penalty for each routes. This penalty increases by a fixed value when a flap occurs, and decreases exponentially when the route is stable. This value ranges from 600 to 270.
<Reuse Value (100-10800)>   Enter to configure the reuse value. If the penalty for a flapping route falls below this value, the route is re-used. The unsuppressing of routes occurs at 10-second increments. This value ranges from 100 to 10800.
Note: Reuse value can be configured only if the HalfLife Time value is set.
<Suppress Value (2000-3999)>   Enter to configure the suppress value. The route is suppressed if the penalty associated with the route exceeds this value. This value ranges from 2000 to 3999.
Note: Suppress value can be configured only if the HalfLife Time and Reuse value are set.
<Max-Suppress Time (1800-10800)   Enter to configure the maximum time (in seconds) a route can be suppressed. This value ranges from 1800 to 10800.
Note: Max-Suppress Time can be configured only if the HalfLife Time, Reuse Value and Suppress Value are set.
default   Enter for BGP default information configuration.
ipv4-unicast   Enter for IPv4 unicast feature configuration for default routing.
local-preference   Enter to configure the default local preference value that is to be sent in updates to internal peers. The preference is sent to all routers and access servers in the local autonomous system. The no form of the command resets the default local preference to its default value.
<Local Pref Value>   Enter a default local preference value that is to be sent in updates to internal peers. This value ranges from 0 to 2147483647.
ecomm-filter   Enter to allow/ filter the extended community attribute while receiving or advertising. The no form of the command removes the filter policy for the extended community attribute.
<ecomm-value(xx:xx:xx:xx:xx:xx:xx:xx)>   Enter to configure the extended community value. This is an octet string value in the form xx:xx:xx:xx:xx:xx:xx:xx.
deny   Enter to deny the route-update with the associated extended community value to pass the filter test. This is the default option.
permit   Enter to allow the route -update with the associated extended community value to pass the filter test.
in   Enter to configure the incoming direction of applied filter.
out   Enter to configure the outgoing direction of applied filter.
ecomm-policy   Enter to configure the Estendedcommunity attribute advertisement policy for specific destination. The no form of the command removes the community attribute advertisement policy for specific destination.
<ip-address>   Enter to configure the route prefix on which extended community policy needs to be applied.
<prefixlen>   Enter to configure the IP prefix length for the destination. These bits are common among all hosts within a network. This value ranges from 1 to 32.
set-add   Enter to send only the configured additive extended communities with associated route.
set-none   Enter to send the associated route without any extended communities.
modify   Enter to remove the associated route with received delete communities and to add the configured additive extended communities.
ecomm-route   Enter to configure an entry in additive or delete extended community table for a given destination. The no form of the command removes the entry from additive or delete community table.
additive   Enter to add an associated community value with the already existing communities in the route update.
delete   Enter to remove the community attribute from the route-prefix when it passes through the filter process.
<ip-address>   Enter to configure the Route prefix on which community policy needs to be applied.
<prefixlen>   Enter to configure the IP prefix length for the destination. These bits are common among all hosts within a network. This value ranges from 1 to 32.
comm-value <value(xx:xx:xx:xx:xx:xx:xx:xx)>   Enter to configure the community attribute value. This value ranges from 4294967041 to 4294967043 or from 65536 to 4294901759.
graceful-restart   Enter to enable graceful restart capability in router which allows forwarding of data packets to continue along known routes, while the routing protocol information is being restored following a processor switch over. When graceful restart is enabled, peer networking devices are informed, through protocol extensions prior to the event. The no form of the command disables the graceful restart capability and resets the restart-time or stalepath-time to the default value
restart-time   Enter to configure the estimated time (in seconds) taken for re-establishing a BGP session after restart. The default value for this should be less than or equal to Hold Time carried in open message.
<(1-4096)<seconds>>   Enter a value for the restart time—it ranges from 1 to 4096 seconds.
stalepath-time   Enter to configure the time (in seconds) until which the router retains the stale routes.
<(90-3600)<seconds>>   Enter a value for the stalepath time—it ranges from 90 to 3600 seconds.
local-preference   Enter to configure an entry in the local preference table. This table contains the value that is to be assigned to the local preference attribute. The defaults are as follows:
  • remote-as - 0
  • direction - in
  • value - 100
  • ip-address - 0.0.0.0
  • prefixlen - 0
<1-100>   Enter a value for the local preference index—it ranges from from 1 to 100.
remote-as <AS no>   Enter to configure the remote Autonomous system number for which the local preference is associated. This value ranges from 1 to 4294967295 or 0.1 to 65535.65535. The no form of the command removes the configured BGP confederation identifier and resets the identifier to its default value.
Note:

When four-bit-asn is enabled, This value ranges from 1 to 4294967295or between 0.1 and 65535.65535.

Note:

When four-bit-asn is disabled, This value ranges from 1 to 65535. or between 0.1 and 0.65535

Note:

When bgp asnotation is enabled, the AS number of the BGP Speaker is displayed in the range 0.1 to 65535.6553.

A value of zero indicates that this entry is not valid and will not be matched for when the Local Pref value for an update is calculated
<ip-address>   Enter to configure the route prefix in the Network Layer Reachability Information on which local-preference policy needs to be applied. The input route ip address can be an ipv4 or an ipv6 address.
<prefixlen>   Enter to configure the number of high-order bits in the IP address. These bits are common among all hosts within a network. This value ranges from 0 to 32 for ipv4 address and 0 to 128 for ipv6 address.A value of zero indicates that the entry is not valid and will not be matched for when the Local Pref value for an update is calculated.
intermediate-as<AS-no list- AS1,AS2,...>   Enter to configure the sequence of intermediate AS numbers through which the route update is expected to travel or a Comma separated list of AS numbers that are to be checked against the AS_PATH attribute of the updates. This value is a list with the maximum size as 100.
value <value>   Enter to configure the local-preference value that needs to be associated with the route-update. This value ranges from 0 to 2147483647.
direction   Enter to specify the direction of the application of local-preference policy with which the entry is to be associated.
in   Enter to indicate a received route-update with other matching attributes such as as-number, intermediate-as numbers.
out   Enter to indicate a route-update that needs to be advertised to peer.
override   Enter to configure an entry in the local preference table. This table contains the value that is to be assigned to the local preference attribute.
med   Enter to configure an entry in BGP4 MED Table and contains the MED values that are to be assigned to routes. The no form of the command deletes the entry from MED Table, BGP4 MED table. The entry will not be matched when the MED value for an update is calculated, if the prefix length is set as zero.The defaults are as follows:
  • remote-as - 0
  • prefixlen - 0
  • direction - in
  • value - 0
<1-100>   Enter a value for the entry containing information about the MED value—it ranges from1 to 100.
remote-as <AS no>   Enter to configure the remote Autonomous system number that identifies the BGP router to other routers and tags the routing information passed along. This value ranges from 1 to 4294967295 or 0.1 to 65535.65535. The no form of the command removes the configured BGP confederation identifier and resets the identifier to its default value.
Note:

When four-bit-asn is enabled, This value ranges from 1 to 4294967295or between 0.1 and 65535.65535.

Note:

When four-bit-asn is disabled, This value ranges from 1 to 65535. or between 0.1 and 0.65535

Note:

When bgp asnotation is enabled, the AS number of the BGP Speaker is displayed in the range 0.1 to 65535.6553.

A value of zero indicates that this entry is not valid and will not be matched for when the Local Pref value for an update is calculated
<ip-address>   Enter to configure the route-prefix IPv4 and IPv6 on which MED policy needs to be applied.
<prefixlen>   Enter to configure the number of high-order bits in the IP address. This is the length of the IP address prefix in the Network Layer Reachability Information (NLRI) field. These bits are common among all hosts within a network. This value ranges from 0 to 32 for ipv4 address and 0 to 128 for ipv6 address. A value of zero indicates that this entry is not valid and will not Be matched for when the MED value for an update is calculated.
intermediate-as<AS-no list- AS1,AS2,...>   Enter to configure the sequence of intermediate AS numbers through which the route update is expected to travel or a Comma separated list of AS numbers that are to be checked against the AS_PATH attribute of the updates. This value is a list with the maximum size as 100.
value <value>   Enter to configure the value assigned to the MED attribute for the route present in NLRI. This value ranges from 0 to 2147483647.
direction   Enter to specify the direction of application of MED policy.
in   Enter to indicate a received route-update with other matching attributes such as as-number, intermediate-as numbers.
out   Enter to indicate a route-update that needs to be advertised to peer.
override   Enter to decide whether the configured MED value will override the received MED value.
nonbgproute-advt   Enter to configure the peer type to whom non-bgp routes can be propagated and controls the advertisement of Non-BGP routes either to the external peer or both to internal and external peer. The no form of the command resets the Non BGP routes advertisement policy to its default value. The Administrator can effectively control the advertisement of the route learnt through Redistribution
external   Enter to indicate that the non-BGP routes can be exported only to external peers. All types of non-bgp routes can be propagated to external peers.
both   Enter to indicate that the non-BGP routes can be propagated to both internal and external peers. This is the default option.
redistribute-internal   Enter to enable IBGP routes to be redistributed to other IGP protocols. The no form of the command disables IBGP routes to be redistributed to other IGP protocols. By default, IBGP route redistribution is disabled.
router-id   Enter to configure fixed BGP router identifier for a BGP-speaking router. If loopback interface exists, the router ID is set to the highest address for loopback interface otherwise it is set to the highest ip configured on the ip interfaces. Peering sessions will be reset if the router ID is changed. BGP router id is a unique number associated with the BGP speaker. This router-id is advertised to other peers and identifies the BGP speaker uniquely. Administrator can set the router-id of BGP to any value. If router-id is changed, then all active peer sessions will go DOWN and will be re-started with the new configured router-id. The no form of the command resets the BGP Identifier of the BGP Speaker to its default value.
A.B.C.D (<ucast_addr>)   Enter an unicast IP address representing BGP identifier. As default, The highest interface address is used as the router id
trap   Enter to enable or disable the BGP trap notification.
enable   Enter to enable the trap notification for the BGP system. When there is any change in the graceful restart state of the router or peer, the BGP system sends the notification messages to the SNMP manager. For every graceful restart, appropriate trace messages is generated. This is the default option.
disable   Enter to disable the trap notification for the BGP system and not send the notification messages to the SNMP manager.
update-delay   Enter to configure the selection deferral time interval. This time interval represents the time (in seconds) until which the router defers its route selection. This time interval should be configured to provide enough time for all peers of the restarting speaker to send all routes to the restarting speaker. The no form of the command resets the time interval to its default value.
<(60-1800)seconds>   Enter a value for the deferral time interval. This value ranges from 60 to 1800 seconds with a default of 60 seconds.
update-filter   Enter to configure an entry in Update Filter Table which contains rules to filter out updates based on the AS from which it is received, Network Layer Reachability Information (NLRI) and AS through which it had passed. The no form of the command deletes the entry from Update Filter Table.The defaults are as follows:
  • remote-as - 0
  • direction - in
  • ip-address - 0.0.0.0
  • prefixlen - 0
<1-100>   Enter a value for the entry containing information about the updates that are to be filtered—it ranges from 1 to 100.
deny   Enter to filter the routes when passing through filter policy test.
permit   Enter to allow the route to pass filter policy test.
remote-as <AS no>   Enter to configure the remote Autonomous system numberthat identifies the BGP router to other routers and tags the routing information passed along. This value ranges from 1 to 4294967295 or 0.1 to 65535.65535. The no form of the command removes the configured BGP confederation identifier and resets the identifier to its default value.
Note:

When four-bit-asn is enabled, This value ranges from 1 to 4294967295or between 0.1 and 65535.65535.

Note:

When four-bit-asn is disabled, This value ranges from 1 to 65535. or between 0.1 and 0.65535

Note:

When bgp asnotation is enabled, the AS number of the BGP Speaker is displayed in the range 0.1 to 65535.6553.

A value of zero indicates that this entry is not valid and will not be matched for when the Local Pref value for an update is calculated
<ip-address>   Enter to configure the route prefix IPv4 and IPv6 in the Network Layer Reachability Information on which the filter policy needs to be applied.
<prefixlen>   Enter to configure the number of high-order bits in the IP address. These bits are common among all hosts within a network. This value ranges from 0 to 32.
intermediate-as<AS-no list- AS1,AS2,...>   Enter to configure the sequence of intermediate AS numbers through which the route update is expected to travel or a Comma separated list of AS numbers that are to be checked against the AS_PATH attribute of the updates. This value is a list with the maximum size as 100.
direction   Enter to specify the direction of the application of filters with which the entry is to be associated.
in   Enter to indicate a received route-update with other matching attributes such as as-number, intermediate-as numbers.
out   Enter to indicate a route-update that needs to be advertised to a peer.

Mode

BGP Router Configuration Mode

Examples

iS5Comm (config-router)# always-compare-med

iS5Comm (config-router)# bgp asnotation dot

iS5Comm (config-router)# bgp client-to-client reflection

iS5Comm (config-router)# bgp bestpath med confed

iS5Comm (config-router)# bgp cluster-id 10.0.0.1

iS5Comm (config-router)# bgp comm-filter 75100 deny in

iS5Comm (config-router)# bgp comm-policy 24.5.0.0 10 set-none

iS5Comm (config-router)# bgp comm-route additive 24.5.0.0 16 comm-value 429490

iS5Comm (config-router)# bgp confederation identifier 1000

iS5Comm (config-router)# bgp confederation peers 100

iS5Comm (config-router)# bgp dampening 1000 300 2000 5000

iS5Comm (config-router)# bgp ecomm-filter 01:01:22:33:23:43:44:22 deny in

iS5Comm (config-router)# bgp comm-policy 24.5.0.0 10 set-none

iS5Comm (config-router)# bgp ecomm-route additive 12.0.0.0 2 ecomm-value 01:01:22:33:44:55:66:77

iS5Comm (config-router)# bgp graceful-restart restart-time 33 stalepath 789

iS5Comm (config-router)# bgp local-preference 5 remote-as 200 21.3.0.0 16 intermediate-as 150 value 250 direction out override

iS5Comm (config-router)# bgp med 5 remote-as 200 212.23.45.0 24 intermediate-as 150 value 50 direction in override

iS5Comm (config-router)# bgp nonbgproute-advt both

iS5Comm (config-router)# bgp redistribute-internal

iS5Comm (config-router)# bgp router-id 10.0.0.1

iS5Comm (config-router)# bgp trap enable

iS5Comm (config-router)# bgp update-delay 90

iS5Comm (config-router)# bgp update-filter 6 deny remote-as 145 72.93.0.0 14 intermediate-as 150 direction in

Parent topic: BGP