[syslog-ng]dns caching

Michael Renner m.renner@inode.at
Tue, 09 Jul 2002 13:28:35 +0200

At 12:16 09.07.2002 +0200, you wrote:

>i've been using syslog-ng for a while, and now that i've setup dnscache
>(from djb) to use syslog instead of his own loggin method (multilog), i've
>found a funny thing that fulls my log files. (dnscache pc and syslog-ng
>hosting pc are different machines, i log through network).
>1- when a dnscache-request is made, dnscache issues a message to syslog-ng.
>2- syslog-ng writes down to the syslog file the new entry, but it does a dns
>lookup (because the log entry is coming from a machine on the network).
>3- loop forever :)
>i don't want to use the use_dns(off) option of syslog-ng, because i wan't
>ips translated. Is there a way that syslog-ng could cache the dns querys, so
>id doesn't do one dns lookup for each line?

This was discussed previously on this list; dns caching shouldn't be the 
job of syslog-ng and would need much "unnecessary" code in syslog-ng; there 
are other programs which are more capable of doing this (dnscache from 
djb). I would suggest that you stick with multilog because dnscache is 
quite verbose and logging these rather unnecessary messages via syslog-ng 
would waste lots of cpu cycles (you don't log your apache access-logs via 
syslog, do you?)

mfg/best regards


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