Removing all related peer group config when removing the peer group itself

[stuh84]

Hey everyone,

So I'm using hier_config within Nautobot, and trying to work out how to remove BGP peer group related config when removing a BGP peer.

Context - using Arista (both CEOS containers and actual EOS devices), using the default Hier Config support for arista EOS with one minor difference: -

"sectional_exiting": [
        {
            "exit_text": "exit",
            "lineage": [
                {
                    "startswith": "router bgp"
                },
                {
                    "startswith": "address-family"
                }
            ]
        }

For example, if I had the following in my BGP config: -

router bgp 4200000001
   neighbor INTERNAL_PG peer group
   neighbor INTERNAL_PG remote-as 4200000001
   neighbor INTERNAL_PG update-source Loopback0
   neighbor INTERNAL_PG bfd
   neighbor INTERNAL_PG ebgp-multihop 4
   neighbor INTERNAL_PG graceful-restart
   neighbor INTERNAL_PG send-community standard extended
   neighbor INTERNAL_PG maximum-routes 24000 warning-only
   neighbor 10.0.254.2 peer group INTERNAL_PG
   neighbor 10.0.254.3 peer group INTERNAL_PG
   neighbor 10.0.254.4 peer group INTERNAL_PG
   address-family evpn
      no neighbor INTERNAL_PG activate
   address-family ipv4
      neighbor INTERNAL_PG activate

The remediation config to remove this peer group is the following: -

router bgp 4200000001
  no neighbor INTERNAL_PG peer group
  no neighbor INTERNAL_PG remote-as 4200000001
  no neighbor INTERNAL_PG update-source Loopback0
  no neighbor INTERNAL_PG bfd
  no neighbor INTERNAL_PG ebgp-multihop 4
  no neighbor INTERNAL_PG graceful-restart
  no neighbor INTERNAL_PG send-community standard extended
  no neighbor INTERNAL_PG maximum-routes 24000 warning-only
  no neighbor 10.0.254.2 peer group INTERNAL_PG
  no neighbor 10.0.254.3 peer group INTERNAL_PG
  no neighbor 10.0.254.4 peer group INTERNAL_PG
  address-family ipv4
    no neighbor INTERNAL_PG activate
    exit
  address-family evpn
    neighbor INTERNAL_PG activate
    exit

However, this could be reduced to just: -

router bgp 4200000001
  no neighbor INTERNAL_PG peer group

I'm struggling to work out which set of rules I need in hier_config to do this. Is it tagging, sectional overwrite, or something else? Can hier_config do this?

Thanks in advance for everyone who takes a look at this!