Vyatta Network OS Documentation

Learn how to install, configure and operate the Vyatta NOS, which helps drive our virtual networking & physical platforms portfolio.

protocols bgp <asn> neighbor <id> ebgp-multihop <ttl>

Allows the configuration of eBGP neighbors not on directly connected networks.

set protocols bgp asn neighbor id ebgp-multihop ttl
delete protocols bgp asn neighbor id ebgp-multihop [ ttl ]
show protocols bgp asn neighbor id

Only directly connected neighbors are allowed.

asn
The number for the AS in which this router resides. The number ranges from 1 through 4294967295.
id
The IPv4 or IPv6 address of a BGP neighbor.
ttl
The time-to-live, or maximum number of hops allowed. The numbers range from 1 through 255.

Configuration mode


protocols {
    bgp asn {
        neighbor id {
            ebgp-multihop ttl
        }
    }
}

Use this command to configure eBGP neighbors that are not on directly connected networks.

For eBGP peers, there are three possible configurations:

  1. By default, outgoing TTL is set to 1 and no checking is done on TTL of incoming packets.
  2. If ebgp-multihop is configured, the TTL for outgoing packets is set to that value and no checking is done on TTL of incoming packets.
  3. If ttl-security hops is configured, the TTL for outgoing packets is set to 255 and the TTL of incoming packets is compared against the value set for ttl-security hops.

Note that ttl-security hops can not be configured at the same time as ebgp-multihop.

Packets are dropped when TTL reaches zero.

Use the set form of this command to allow connections to eBGP peers residing on networks that are not directly connected.

Use the delete form of this command to restrict connections to directly connected peers.

Use the show form of this command to view BGP neighbor configuration settings.