Cisco Nexus AS23456

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1

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
2

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…

3

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