Apache sign in lengthy format, saved on multiple servers, relevant towards the same domain. I have to merge them together in chronological order so AWstats or something like that similar can produce a log.

Obviously, saying how you can just throw them at random in a parsing tool to create an access log will be a sufficient answer too.

http://awstats.sourceforge.net/docs/awstats_faq.html#LOADLOG

AWstats features a script to get this done. For individuals running load balancers and multiple application servers, AWstats just type of handles it for you personally. The correct answer is awesome.