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I just changed my Apache log behavior because it was making me having very BIG files...

So I now use cronolog to split my logs to log/httpd/2012/11/access_2012.11.30.log for exemple, pattern : %Y/%m/access_%Y.%m.%d.log

I now want to split my old 42GB file to the same structure but really don't know how to do that efficiently.

I tried some simple commands with cat, egrep, awk... but really don't know how to handle all that in a more powerful script.

Here is how the log looks like :

x.x.237.134 - - [08/Apr/2011:14:43:09 +0200] "GET...
x.x.50.15 - - [08/Apr/2011:14:43:09 +0200] "GET...
x.x.254.19 - - [28/Feb/2012:15:24:48 +0100] "GET...

So I need for yeah line to get :

  • year %Y (ex. 2012)
  • month %m (ex. 11)
  • day %d

And to push out the entire line to : %Y/%m/access_%Y.%m.%d.log

Can someone give me clues to get that working ?

Thanks a lot for your interest.

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1 Answer 1

You could grab one of the existing Apache access log splitters from the interweb, alternatively you could hack something together in a few lines of sh, php, phyton, or perl e.g.

# Purpose: Split an Apache HTTPD access log up into daily files, with each file placed
#          in a year and month specific directory.
my @aFields;
my $sLogDir='/var/log/httpd';
my $sCurrentDay="1901.01.01";
my $sCurrentMonth="1901/01";
my %mon2num = qw(
  Jan 01  Feb 02  Mar 03  Apr 04  May 05  Jun 06
  Jul 07  Aug 08  Sep 09  Oct 10  Nov 11  Dec 12
open (FILE,"$sLogDir/access_log") || die("Error: Could not open file - $sLogDir/access_log !");
while (my $sLine = <FILE>) {
  @aFields=split(' ', $sLine);
  @aFields=split(':', $aFields[3]);
  @aFields=split('/', $aFields[0]);
  $aFields[0] =~ s/^\[//;
  $aFields[1] = $mon2num{$aFields[1]};
  if ($sCurrentMonth !~ /$aFields[2]\/$aFields[1]/) {
    print "Processing: $aFields[2]/$aFields[1]\n";
    $sCurrentMonth = "$aFields[2]/$aFields[1]";
    unless(-d "$sLogDir/$aFields[2]"){
      mkdir "$sLogDir/$aFields[2]" or die("Error: Couldn't create - $sLogDir/$aFields[2]");
    unless(-d "$sLogDir/$sCurrentMonth"){
      mkdir "$sLogDir/$sCurrentMonth" or die("Error: Couldn't create - $sLogDir/$sCurrentMonth");
  if ($sCurrentDay !=  "$aFields[2].$aFields[1].$aFields[0]") {
    $sCurrentDay = "$aFields[2].$aFields[1].$aFields[0]";
    open (NEW,">>$sLogDir/$sCurrentMonth/access_${sCurrentDay}.log") || die("Could not open file - $sLogDir/$sCurrentMonth/access_${sCurrentDay}.log !");
    print NEW $sLine;
print "All done :o)\n\n";
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