Ping Checks Fail in Cacti with iputils-20100418

Introduction

It appears the output of ping has changed in this release of iputils from referring to the icmp seq numbers as icmp_seq to icmp_req which obliterates the ping.pl script that cacti uses to do pings of servers it watches and results in NaN values.

The Fix

The fix is quite simple: change the seq to req in the grep line of ping.pl but the following fix is probably more versatile (and will be checked for upstream).

*** a/ping.pl 2010-07-09 17:33:46.000000000 -0500
--- b/ping.pl 2010-10-24 18:22:16.325881546 -0500
*************
*** 4,10 ****
  $host = $ARGV[0];
  $host =~ s/tcp:/$1/gis;

! open(PROCESS, "ping -c 1 $host | grep icmp_seq | grep time |");
  $ping = <process>;
  close(PROCESS);
  $ping =~ m/(.*time=)(.*) (ms|usec)/;
--- 4,10 ----
  $host = $ARGV[0]
  $host =~ s/tcp:/$1/gis;

! open(PROCESS, "ping -c 1 $host | grep -E icmp_/(r\|s\)eq | grep time |");
  $ping = <process>;
  close(PROCESS);
  $ping =~ m/(.*time=)(.*) (ms|usec)/;

Conclusion

Sometimes things just break because of small changes. This is a simple example of that and the quick fix for the annoyance of not recording ping times in Cacti.