Monitor instances of Apache Web server

[mda2]

Some weeks ago we have performance problems with 4 apache webservers. When start investigate my question is arround of the number of clients connecting and your states. To determine it, I quickly think... count it from Apache-status (previously enabled). For the code like this:

#!/usr/local/bin/perl -w
#
#
$|++;

use LWP::Simple;


 my $server = shift || 'wks%02s.click21.com.br';
 my $count  = shift || 4;


 my @Status = qw( _ S R K D L G . );
 my ( %Info, %Status );
 my @Info = qw( BusyServers IdleServers CPULoad ReqPerSec );


 my $data;
 my $n;

 my $Mask = "http://$server/server-status?auto";

  printf " " x 14;
  map { printf(" %s  ", $_ ) } @Status;
  print "\t";
  map { printf(" %4s", substr($_,0,4) ) } @Info;
  print "\n";

  for( $n = 1; $n <= $count; $n++ ) {

    $data = get(sprintf($Mask, $n));
    
    foreach my $l ( split(/\n/, $data) ) {
        $Info{$1} = $2
            if ( $l =~ m/^([^:]+):\s+(.*)/ );
    }

    # Define group status
    foreach ( @Status ) {
        $Status{$_} = ( $Info{Scoreboard} =~ s/$_//g ) || '-';
    }

    printf "%10s: ", substr( sprintf($server, $n), 0, 10 );

    map { printf(" %3s", $Status{$_}) } @Status;

    print "\t";
    map { printf(" %-4s", substr($Info{$_},0,4) ) } @Info;

    print "\n";

  }

Data samples:

Data sample from /apache-status?auto

Total Accesses: 2144860
Total kBytes: 6671882
CPULoad: .38901
Uptime: 170975
ReqPerSec: 12.5449
BytesPerSec: 39959.1
BytesPerReq: 3185.29
BusyServers: 49

IdleServers: 23
Scoreboard: WWWWW___WR__WW_W_WWWWWD_R__WWWW_WWWWWWRWW__WW____W_W_WWWWR
+RWWWWW_R___WRR....

Results:

    
--- on demand result --
               _   S   R   K   D   L   G   .     Busy Idle CPUL ReqP
wks01.clic:   25   -  14   -   1   -   - 216     44   25   .449 12.6
wks02.clic:   31   -   3   -   1   -   - 221     28   31   .398 12.0
wks03.clic:   15   -   2   -   1   -   - 238     22   15   .814 11.0
wks04.clic:   17   -   4   -   1   -   - 1002    22   17   .535 10.8

Or, to other server:

Or:

$ ./monitor webmail%s.click21.com.br 8
               _   S   R   K   D   L   G   .     Busy Idle CPUL ReqP
webmail1.c:    6   -   4  22   -   1   - 223     47   6    3.27 11.7
webmail2.c:    8   -   5  37   -   -   - 206     70   8    1.70 14.0
webmail3.c:   11   -   4  43   -   -   - 198     68   11   1.82 13.7
webmail4.c:   14   -   2  33   -   2   - 205     60   14   2.61 12.5
webmail5.c:    9   -   3  22   -   -   - 222     51   9    1.50 14.2
webmail6.c:    2   -   6  75   -   -   - 173     111  2    2.33 12.9
webmail7.c:   11   -   -  26   -   -   1 218     54   11   .044 10.9
webmail8.c:    9   -   1  31   -   -   2 213     59   9    .051 11.1

More info about:

Apache Status module

LWP::Simple

This code provide some data to diagnostics configuration problems.

More resources are great, if needs to explain by slot/child of apache, but itīs more hard to do, and need HTML::Parser.

[mda2]

This node is my work, to get realtime data from my servers, and to add more information and tools, see Apache-Tools, to monitor your WebServers (Perl too :D ).
One demo and /server-status from Apache.org are available!