fping was updated last month (2012-08-19) to version 3.3. Output statistics were directed to stdout instead of stderr so Smokeping (2.6.8) was not updating RRD files as a result.

This is fixed in fping 3.4 (2012-09-04) but RPMforge for CentOS 6 repository doesn’t contain latest version so if you experience this problem just downgrade above-mentioned package.

$ sudo yum downgrade fping
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Downgrade Process
Loading mirror speeds from cached hostfile
 * base: centos.hitme.net.pl
 * extras: centos.hitme.net.pl
 * rpmforge: mirror.nl.leaseweb.net
 * updates: centos.hitme.net.pl
Resolving Dependencies
--> Running transaction check
---> Package fping.x86_64 0:3.1-1.el6.rf will be a downgrade
---> Package fping.x86_64 0:3.3-1.el6.rf will be erased
--> Finished Dependency Resolution
Dependencies Resolved
 Package        Arch            Version                 Repository         Size
 fping          x86_64          3.1-1.el6.rf            rpmforge           45 k
Transaction Summary
Downgrade     1 Package(s)
Total download size: 45 k
Is this ok [y/N]: y
Downloading Packages:
fping-3.1-1.el6.rf.x86_64.rpm                            |  45 kB     00:00
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
  Installing : fping-3.1-1.el6.rf.x86_64                                    1/2
  Cleanup    : fping-3.3-1.el6.rf.x86_64                                    2/2
  Verifying  : fping-3.1-1.el6.rf.x86_64                                    1/2
  Verifying  : fping-3.3-1.el6.rf.x86_64                                    2/2
  fping.x86_64 0:3.3-1.el6.rf
  fping.x86_64 0:3.1-1.el6.rf

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