# neighbor update-source

#### Syntax

neighbor { ipAddress | ipv6Address | peerGroupName } update-source
{ interfaceType interfaceSpecifier | updateSourceAddress | updateSourcev6Address }

no neighbor { ipAddress | ipv6Address | peerGroupName } update-source
[ interfaceType interfaceSpecifier | updateSourceAddress | updateSourcev6Address ]

#### Release Information

Command introduced before JunosE Release 7.1.0.
ipv6Address variable and updateSourcev6Address variable added in JunosE Release 8.0.0.

#### Description

Allows a BGP session to use the IP address of a specific operational interface as the source address of TCP connections used by BGP. This command takes effect immediately and automatically bounces the BGP session. If you specify an interface in this command and later remove the interface, this command is also removed from the router configuration. The no version restores the interface assignment to the closest interface.

| Note: Removing an interface that was specified in this command effectively removes this command from the router configuration as well.

#### Options

- ipAddress—IP address of BGP neighbor
- ipv6Address—IPv6 address of BGP neighbor
- peerGroupName—Name of a BGP peer group. If you specify a BGP peer group by using the peerGroupName argument, all the members of the peer group inherit the characteristic configured with this command, unless it is overridden for a specific peer.
- interfaceType—Interface type; see Interface Types and Specifiers
- interfaceSpecifier—Particular interface; format varies according to interface type; see Interface Types and Specifiers
- updateSourceAddress—Source IP address
- updateSourcev6Address—Source IPv6 address

#### Mode

Address Family Configuration, Router Configuration

#### Related Documentation

- Configuring BGP Signaling for L2VPNs in the JunosE BGP and MPLS Configuration Guide