I can confirm working syslog integration between the latest Observium version and several ASR9K’s running various versions of IOS-XR. 

Didn’t need to do anything special. 

Here is excerpt from syslog-ng.conf

destination d_observium {

program("/opt/observium/syslog.php" template ("$HOST||$FACILITY||$PRIORITY||$LEVEL||$TAG||$YEAR-$MONTH-$DAY $HOUR:$MIN:$SEC||$MSG||$PROGRAM\n") template-escape(yes));

};

log {

source(s_net);

destination(d_observium);

};

I guess Observium is doing an IP lookup as you mentioned to match the hostname I have in Observium. The configured hostnames in the routers do not match what I have in Observium.  I probably need to change that but it is currently working.  

I just need the following config in the ASR9K’s pointing to Observium

logging 192.168.1.1 vrf default

From: Markus Klock <markus@best-practice.se>
Reply-To: "observium@observium.org" <observium@observium.org>
Date: Friday, September 19, 2014 at 12:36 AM
To: "observium@observium.org" <observium@observium.org>
Subject: [Observium] syslog-ng implementation and Cisco ASR9K

Hey guys!

I´m setting up syslog-ng implementation and it works great for all my Cisco IOS-devices, however most of the devices in my network is Cisco ASR9K-routers running IOS-XR and it seems syslog from them wont go in to Observium.

I did a quick look in the syslog-messages from the ASR9Ks and it seems IOS-XR actrually don't use its hostname as hostname but instead use its active routeprocessors name (wtf cisco?!) making the syslog messages look something like this:

RP/0/RSP0/CPU0:Nov 28 23:56:53.826 : config[65710]: %SYS-5-CONFIG_I : Configured from console by console

Now there is a command that let you add a "hostname prefix" to the syslog messages, which means that I can type my own custom string as hostname for syslog, sadly it still just adds it before the RPS-id making the messages like this:

router1 RP/0/RSP0/CPU0:router:Nov 28 23:56:53.826 : config[65710]: %SYS-5-CONFIG_I : Configured from console by console
This of course makes it impossible for Observium to match the syslogged hostname to a hostname in the database. 
I took a look in the observium syslog-code and if I understand it correctly, if it fails to match the hostname it does a fallback and tries if maybe the IP-address is used as hostname and try to match it against a host in the database?
In that case maybe I could change the syslog-ng template that forwards the data to Observium to instead use source IP instead of hostname?
destination d_observium { 
	program("/opt/observium/syslog.php" template ("$HOST||$FACILITY||$PRIORITY||$LEVEL||$TAG||$YEAR-$MONTH-$DAY $HOUR:$MIN:$SEC||$MSG||$PROGRAM\n") template-escape(yes)); 
I tried change $HOST to $HOST_FROM and $SOURCEIP but no luck so far.
Am I even on the right track here? Could something like this work to make my idiotic ASR9Ks show up in the Observium syslog?
Thanks in advance for any advice
/Markus

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