Cisco Nexus AS23456

Wondering if anyone else has this issue. We have a Nexus C93108TC-EX with a couple BGP connections. The local AS is returning 23456 while the remote AS numbers are correct. They show up as eBGP connections as a result of this instead of the iBGP connections they should be.

Component | Version
--------- | -------
LibreNMS  | 1.67-82-g2a515d308
DB Schema | 2020_09_22_172321_add_alert_log_index (174)
PHP       | 7.3.18-1+0~20200515.59+debian9~1.gbp12fa4f
Python    | 3.5.3
MySQL     | 10.1.44-MariaDB-0+deb9u1
RRDTool   | 1.6.0
SNMP      | NET-SNMP 5.7.3

[OK]    Composer Version: 1.10.13
[OK]    Dependencies up-to-date.
[OK]    Database connection successful
[OK]    Database schema correct

AS23456 is the 4bytes AS placeholder, which is displayed whenever a 4Bytes AS is unsupported. From BGP point of view, it allows to mix devices with and without support for extended 4bytes ASes.

Seems surprising to have a broken AS4byte support on a Cisco Nexus 9k. Would be interesting to dig into the snmp replies to see if both the placeholder and the real AS are replied in different OIDs…

That was my thought too. I’ll do some digging later when I get time.