Remove a ipv6 neighbor from a ipv4 address family BGP

[imfvieira]

Hello,

Checking configuration int some routers we found some ipv6 neighbors inside address family ipv4. It´s a 7606-S with version 15.3(1)S2.

I was searching for the way to remove only the neighbor ipv6 inside this ipv4 address family. The neighbors are active at ipv6 address family.

Is there a way to do it without removing all neighbor configurations? or at least with few impact at configurations? Actually they are "no activated"

!===config===!

address-family ipv4
.....
  no neighbor X:X:X:X::X activate
  no neighbor Y:Y:Y:Y::Y activate
  no neighbor Z:Z:Z:Z::Z activate

!

address-family ipv6

....

  neighbor X:X:X:X::X activate
  neighbor Y:Y:Y:Y::Y activate
  neighbor Z:Z:Z:Z::Z activate

!===endofconfig===!

Thanks.

[Peter Paluch · Accepted solution]

Hi,

I believe there is no way of removing the IPv6 neighbors from address-family ipv4. However, when you think about it, removing them from the address-family ipv4 is identical to having them there as no neighbor ipv6-address - exactly the way your configuration is done now.

Keep in mind that an address-family section defines the content exchanged with a particular neighbor. It does not define that neighbor, rather, it only specifies what content shall be exchanged with that neighbor. For each neighbor that is defined, your router needs to know what content shall be exchanged with it. It is therefore quite logical to see the IPv6 neighbors in address-family ipv4 in the no form.

Apart from making your configuration a bit more verbose, there is no harm in having IPv6 neighbors in the address-family ipv4 section with the no modifier, quite the contrary: It tells your BGP process not to try to exchange IPv4 networks with those IPv6 neighbors, which is probably what you want anyway.

Best regards,
Peter

[imfvieira]

Thanks for the answer Peter.