Pretty sure the problem is in the REGEX attribute in the [snmp-trap-host] stanza. You defined the group as a non-capturing group, which means the $1 group in the FORMAT attribute will always be blank. Furthermore, even if you remove the "?:" from the regex statement, I still don't think the group will capture the entire IP address. I recommend updating your regex code and re-testing it using an online regex testing tool. I really like this site: http://www.myezapp.com/apps/dev/regexp/show.ws ... View more