Hi,

I have a VNX5500 and also have the following AntiVirus environment configuratio:

VNX5700
  NAS OS Version:7.0.40.1(CS and DataMover)
  server_2:Active (configured Virus check / refer AV Server1 and AV Server2 )
  server_3:Active (configured Virus check / refer AV Server1 and AV Server2 )
  server_4:Standby

AV Server
  OS : Windows Server 2008 R2 Standard (64bit)
  Software :
    CelerraCifsMgmt v4.4.0.4     Ver:4.4.0.4
    EMC VNX Event Enabler 4.9.3(32bit)  Ver:4.9.30
    Symantec Scan Engine(32bit)         Ver:5.2.11.131
    Symantec Endpoint Protection Ver:12.1.1000.157
    LiveUpdate 2.6(Symantec Corporation) Ver:2.6.17.0

The following messages occasionally are listed in DataMover server_log.

#server_2 server_log
   2012-01-20 20:05:57: 81878122502: VC: 3: 6: No virus checker server is available. Virus checking is stopped.
   2012-01-26 12:20:47: 81878122502: VC: 3: 6: No virus checker server is available. Virus checking is stopped.
   2012-01-26 20:14:30: 81878122502: VC: 3: 6: No virus checker server is available. Virus checking is stopped.

Virus checking can be worked properly by restarting the VC client service on DM.
However, the problem recur sometime soon.

I got a tcpdump trace on DataMover and analyzed the trace.
From the trace, I noticed that from time to time the CAVA servers taking up to 12 seconds to start servicing this VC heartbeat requests.
The traces don't give indication and inside view as to the cause for this 12 seconds delay on CAVA servers.

I think that this issue may depend on AV server's environment.

Could you please help me.