[FROG] frr 5.0.2, remove-private-AS and ebgp multihop

[Chris Malton]

Hi all,

Weird one here:

In my config I have an eBGP Multihop peer, and for some reason, despite 
the config looking like this:

router bgp 65001
  neighbor w.x.y.z remote-as nnnnn
  neighbor w.x.y.z local-as 205804
  neighbor w.x.y.z description Upstream - Peering Router - b
  neighbor w.x.y.z ebgp-multihop 2
  neighbor w.x.y.z disable-connected-check
  neighbor w.x.y.z update-source 81.187.56.158
  address-family ipv4 unicast
   neighbor w.x.y.z remove-private-AS all replace-AS

nnnnn is the correct peer ASN.

The resulting PCAP in wireshark shows:

Path Attribute - AS_PATH: 205804 65001
     Flags: 0x50, Transitive, Extended-Length, Well-known, Complete
     Type Code: AS_PATH (2)
     Length: 10
     AS Path segment: 205804 65001
         Segment type: AS_SEQUENCE (2)
         Segment length (number of ASN): 2
         AS4: 205804
         AS4: 65001

I am convinced I have done something wrong, as I expected FRR to strip 
65001 from the sequence.

I'm running frr 5.0.2 on a pfSense (so alas, upgrading to 6 isn't an 
option at the moment).

Any hints what I've done wrong - or is this a known bug?

Regards,

Chris Malton

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