Linux

please, describe what the issue is about in the issue itself

Could it be possible that it's by design ?
For me "Zabbix" as a tag is ok, and "Agent (daemon)[32614]: zabbix_agentd listener started" also looks as a good sentence.

Otherwise the sentence will start from "(daemon) ..." which would look not ideal, so the sentence should be improved as well.

Also, first letter "Z" in "Zabbix" probably should be small "z".

Well, looks like would be indeed good to remove/replace the space.
Then we need to remove the " (daemon)" word to parse correctly processes PID.

According to RFC5424 6.2.5. APP-NAME using 'zabbix' for all daemons might be okay.
Anyway, I'd prefer to have the possibility to filter for the respective daemon via APP-NAME.

Thanks for pointing to the RFC, Marc! Indeed, space is not allowed in APP NAME.
How about changing APP NAMEs:
"Zabbix Agent" -> "zabbix_agent"
"Zabbix Proxy" -> "zabbix_proxy"
"Zabbix Server" -> "zabbix_server"
"Zabbix Get" -> "zabbix_get"
"Zabbix Sender" -> "zabbix_sender" ?
Then they conform to standard and also match names of Zabbix binaries.

sounds reasonable to me.

Available in the development branch svn://svn.zabbix.com/branches/dev/ZBX-4243.

Fixed in versions pre-2.3.0 rev. 41024.

Reopened to implement the fix in all supported Zabbix versions: 1.8, 2.0, 2.2 to conform to RFC-5424.

it might be worth noting that new "app names" also include pid in square brackets, for example :

zabbix_server[12345]

while rfc seems to suggest using a single space to separate id, almost all other software we reviewed uses such an approach.

also, some things aren't very consistent in their log messages, for example :

/USR/SBIN/CRON[4007]: pam_unix(crond:session): session closed for user root
/usr/sbin/cron[6716]: pam_unix(crond:session): session opened for user root by (uid=0)

Available in the development branches svn://svn.zabbix.com/branches/dev/ZBX-4243-18, svn://svn.zabbix.com/branches/dev/ZBX-4243-20, svn://svn.zabbix.com/branches/dev/ZBX-4243-22.

Looks good. When merging into stable branches, the original ChangeLog entry should probably be removed from 2.3.0 and added for each stable version.

Fixed in versions pre-1.8.20 rev.41126, pre-2.0.11 rev.41128, pre-2.2.2 rev.41130, pre-2.3.0 rev.41133.

Documented at
https://www.zabbix.com/documentation/1.8/manual/about/what_s_new_1.8.20?&#daemon_improvements
https://www.zabbix.com/documentation/1.8/manual/about/installation_and_upgrade?&#for_version_1820
https://www.zabbix.com/documentation/2.0/manual/introduction/whatsnew2011?&#daemon_improvements
https://www.zabbix.com/documentation/2.0/manual/installation/upgrade_notes_2011#syslog_application_names_change
https://www.zabbix.com/documentation/2.2/manual/introduction/whatsnew222?&#daemon_improvements
https://www.zabbix.com/documentation/2.2/manual/installation/upgrade_notes_222?&#syslog_application_names_change