The Samba probe checks the nmbd daemon using the nmblookup program for each interface specified within the smb.conf file.
The Samba probe checks the smbd daemon using the smbclient program together with the samba-fault-monitor-user to access the scmondir share.
If smbclient cannot connect, there could be network/server issues causing smbclient to fail. These errors maybe transient and correctable within a few seconds. Therefore before a failure is called by the probe, smbclient is retried within 85% of the available Probe_timeout less 15 seconds, which is approximately the time-out for the first smbclient failure.
However, doing this is only realistic if Probe_timeout=30 seconds or more. If Probe_timeout is below 30 seconds then smbclient is tried only once.