Ping Failing from collector to device and back?

6 minutes ago, Dominique said:

Hello I am getting errors:“VIPEIEEMP01 is suffering ping loss. 100.0% of pings are not returning, placing the host into critical state.”

“The host VIPEIEEMP01 is down. No data has been received”

 If I do a ping from the command prompt of the Client to the Collector  it works

The firewall is wide opened!!!

What did I miss?

Thanks,

Dom

This is an old bug.  I tried (and keep trying) to get it fixed for years, but no luck so far.  The problem is that any firewall keeps a session table.  ping is not session-based like TCP, but firewalls still keep track of ICMP ID and use timers to invalidate sessions.  Same for UDP (SNMP).  The LM collector code is "lazy" and does not generate new session-equivalents for successive checks, so eventually the traffic is dropped by the firewall because it is matched to an invalid session.  You can workaround this by restarting the collector.  For SNMP they have recently added some knobs in the collector config to help, but for ICMP it is still messed up.