Cisco XR BGP neighbor group

Question

I have a problem with understanding the neighbor-groups in Cisco IOS XR. I will describe it on below example:

router bgp 10429 
 bfd minimum-interval 300
 !
 neighbor-group IBGP
  remote-as 10429
  address-family ipv4 unicast
   route-policy pass-all in
   route-policy pass-all out
  !
  address-family l2vpn vpls-vpws
   route-policy block-all in
   route-policy block-all out
  !
 !
 neighbor 187.100.0.89
  remote-as 65200
  use neighbor-group IBGP
  description TEST
  address-family ipv4 unicast
 !
!

1. Remote-as will be overwritten by neighbor-group?
2. Does neighbor inherit pass-all in and pass-all out policies because contain 'address-family ipv4 unicast' row?
3. Does neighbor inherit policies, which are under 'address-family l2vpn vpls-vpws'?

In my current understanding:
1. No
2. Yes
3. No, because there is no row 'address-family l2vpn vpls-vpws' under the neighbor.

Answer 1

Here are my answers:

1. No, remote-as value (of neighbor 187.100.0.89) stays unchanged of 65200.
2. Yes, even you do not have 'address-family ipv4 unicast'.
3. Yes, the neighbor inherits policies under 'address-family l2vpn vpls-vpws'.

You can verify all the answers by using commands:

#show bgp neighbors 187.100.0.89 configuration    

  neighbor 187.100.0.89
     remote-as 65200             []
     description TEST            []
     address-family IPv4 Unicast []
      policy pass-all in         [n:IBGP]
      policy pass-all out        [n:IBGP]
     address-family L2VPN VPLS   [n:IBGP]
      policy block-all in        [n:IBGP]
      policy block-all out       [n:IBGP]

#show bgp neighbors 187.100.0.89 inheritance

  Session:      n:IBGP
  IPv4 Unicast: n:IBGP
  L2VPN VPLS:   n:IBGP

#show bgp neighbors  187.100.0.89

  BGP neighbor is 187.100.0.89
  Remote AS 65200, local AS 10429, external link
  Description: TEST
  ...
  For Address Family: IPv4 Unicast
  BGP neighbor version 0
  Update group: 0.1 Filter-group: 0.0  No Refresh request being processed
  Route refresh request: received 0, sent 0
  Policy for incoming advertisements is pass-all
  Policy for outgoing advertisements is pass-all
  ...
  For Address Family: L2VPN VPLS
  BGP neighbor version 0
  Update group: 0.1 Filter-group: 0.0  No Refresh request being processed
  Community attribute sent to this neighbor
  Extended community attribute sent to this neighbor
  Route refresh request: received 0, sent 0
  Policy for incoming advertisements is block-all
  Policy for outgoing advertisements is block-all

I hope it is useful and answers your questions. Please check Cisco docs about Template Inheritance Rules for BGP on IOS-XR.