Administrator Guide

ROUTER-BGP Mode
shutdown address-family-ipv6-unicast
When you configure BGP, you must explicitly enable the BGP neighbors using the following commands:
neighbor {ip-address | peer-group name} remote-as as-number
neighbor {ip-address | peer-group-name} no shutdown
For more information on enabling BGP, see Enabling BGP.
When you use the shutdown all command in global configuration mode, this command takes precedence over the
shutdown address-family-ipv4-unicast, shutdown address-family-ipv4-multicast, and shutdown
address-family-ipv6-unicast commands. Irrespective of whether the BGP neighbors are disabled earlier, the
shutdown all command brings down all the configured BGP neighbors.
When you issue the no shutdown all command, all the BGP neighbor neighbors are enabled. However, when you re-enable
all the BGP neighbors in global configuration mode, only the neighbors that were not in disabled state before the global
shutdown come up.
Meaning, BGP neighbors corresponding to the IPv4 unicast or multicast address family and the IPv6 unicast address family that
were explicitly disabled before the global shutdown remains in disabled state. Use the no shutdown address-family-
ipv4-unicast, no shutdown address-family-ipv4-multicast, or no shutdown address-family-ipv6-
unicast commands to enable these neighbors.
NOTE: This behavior applies to all BGP neighbors. Meaning, BGP neighbors that were explicitly disabled before global
shutdown also remain in disabled state. Enable these neighbors individually using the no shutdown command.
Route Map Continue
The BGP route map continue feature, continue [sequence-number], (in ROUTE-MAP mode) allows movement from one
route-map entry to a specific route-map entry (the sequence number).
If you do not specify a sequence number, the continue feature moves to the next sequence number (also known as an “implied
continue”). If a match clause exists, the continue feature executes only after a successful match occurs. If there are no
successful matches, continue is ignored.
Match a Clause with a Continue Clause
The continue feature can exist without a match clause.
Without a match clause, the continue clause executes and jumps to the specified route-map entry. With a match clause and a
continue clause, the match clause executes first and the continue clause next in a specified route map entry. The continue
clause launches only after a successful match. The behavior is:
● A successful match with a continue clause—the route map executes the set clauses and then goes to the specified route
map entry after execution of the continue clause.
● If the next route map entry contains a continue clause, the route map executes the continue clause if a successful match
occurs.
● If the next route map entry does not contain a continue clause, the route map evaluates normally. If a match does not occur,
the route map does not continue and falls-through to the next sequence number, if one exists
Set a Clause with a Continue Clause
If the route-map entry contains sets with the continue clause, the set actions operation is performed first followed by the
continue clause jump to the specified route map entry.
● If a set actions operation occurs in the first route map entry and then the same set action occurs with a different value in a
subsequent route map entry, the last set of actions overrides the previous set of actions with the same set command.
● If the set community additive and set as-path prepend commands are configured, the communities and AS
numbers are prepended.
Border Gateway Protocol (BGP)
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