C5x devices have misformatted syslog

I have three C5x devices using the 2.8.x firmware. They are all set to send remote syslog to an ip address on our LAN. However, these three (and ONLY these three – every other device using this rsyslog server appears to work fine) are giving errors in the log file. And worse, this is causing the device’s ip address to not be logged, and so librenms isn’t picking up their syslog data.

A slightly-redacted version of one example:

Nov 3 09:50:10 RsyslogServer syslog-ng[21753]: Error processing log message: <4>1 2020-11-03 14:50:10 (UTC +0000). C5x_device Airspan_C5x[3125412247] AlarmThreshold - Ethernet link up(1000/Full)

whereas a C5x device (this one on the 2.5.x firmware) gets correctly logged like this:

Nov 3 11:29:48 ip.ip.ip.ip Mimosa_C5x[3115623549]: Ethernet link up (1000/Full)

As I understand it, A5 & C5* devices must run “matching” firmwares, ie. 2.5.x with 2.5.x and 2.8.x with 2.8.x

My syslog-ng installation is fairly bog-standard, the only modifications to /etc/syslog-ng/syslog-ng.conf were the ones to interlink it with LibreNMS

I have to assume then that there is no fix for this, neither by tweaking something on the C5x, nor by tweaking something in syslog-ng.

I would chat with Mimosa about this, I don’t have syslog running from any devices running 2.8.x otherwise I would check to confirm.

If the data isn’t getting logged, is it because the formatting is different and a new RegEX needs to be made so LibreNMS gets the correct info out of the message?