logmerge
Logmerge is hosted on RubyGems.org starting with version 1.0.1
(Original) Rubyforge Project:
rubyforge.org/projects/rctools/
About
Logmerge contains two utilities logmerge and ip2name. logmerge merges Apache access logs into one log ordered by date. ip2name performs DNS lookups on Apache access logs using multiple threads and Ruby’s DNS resolver library to speed through log files.
Using logmerge
Simply pass in all the logs you want to merge on the command line. logmerge gives you the merged log on STDOUT.
logmerge hal/access.log nestor/access.log herbie/access.log > merged.log
Note that logmerge expects the input log files to be ordered by date.
Using ip2name
Simply pass in the log files you want to perform DNS lookups on the command line or via STDIN. ip2name gives you the looked-up log lines on STDOUT.
ip2name < merged.log > resolved.log
ip2name merged.log > resolved.log
In order to speed DNS lookups, ip2name creates a .name_cache file in the current directory. ip2name uses double the DNS record TTL value so rapidly-changing names may not be correctly resolved.