[j-nsp] Mixing v4/v6 neighbors in BGP groups

[Job Snijders]

On Fri, Jun 29, 2018 at 8:26 PM, Rob Foehl <rwf at loonybin.net> wrote:
> On Fri, 29 Jun 2018, Job Snijders wrote:
>
>> For the purpose of inter-domain routing I'd advise against mixing warm
>> mayonnaise and jagermeister. uh.. i mean IPv4 and IPv6.
>>
>> Keeping things separate maybe makes debugging easier.
>
>
> I may have been insufficiently specific...  I'm referring to:
>
> group example {
>     neighbor 192.0.2.0;
>     neighbor 2001:db8::;
> }
>
> vs.
>
> group example-ipv4 {
>     neighbor 192.0.2.0;
> }
>
> group example-ipv6 {
>     neighbor 2001:db8::;
> }
>
>
> The former is (operationally) simpler to deal with, until it isn't -- think
> "deactivate group example", etc.  I'm tempted to just be explicit about the
> split everywhere, but I already spend enough time explaining that there are
> two of everything and it's been that way for a while now...

I'd be explicit about this split. You'll maybe have routing policies
applied on the group level, perhaps also on the neighbor level - maybe
not always. What happens when you put a policy designed for only IPv4
on IPv6 neighbors? What will happen on the other vendors you'll later
pull into your network?

If the network is automated the split doesn't matter that much anyway.

Kind regards,

Job