Zabbix 3.4 agent unreachable for 5 minutes

[dchall]

Hi, I'm running Zabbix 3.4, monitoring about 30 hosts. Since updating to 3.4, some (not all) Windows hosts trigger "unreachable for 5 minutes". That status isn't flapping, it stays in Problem mode for days. The alerts don't clear upon restarting the agent on the hosts, network connectivity between the hosts and the server seems fine,and there don't appear to be any relevant items in the agent or server logs. Zabbix server performance looks fine, with no items in the queue graph. The only thing that restores connectivity is restarting the zabbix-server service. Then it works fine for a day or two until hosts start failing again.

I've increased the "Timeout" setting on the server; increased the StartAgents on the host, and increased the BufferSend and BufferSize values. I've also tried removing the hosts and letting them re-register.

Any suggestions or logs I should attach? Assistance appreciated.

[Atsushi]

What version are you using?
If the version you are using is 3.4.0, please upgrade to version 3.4.1 or later promptly.

Relase notes 3.4.1:

https://www.zabbix.com/rn3.4.1

[dchall]

I was on 3.4.0. I've updated to 3.4.1 and will keep an eye on it.

Thanks,
Chris

[dchall]

Over the course of the weekend the issue hasn't popped up again. Looks like the update to 3.4.1 solved it. Thanks!

[LaurisG]

I have same problem with zabbix agent on Server 2008 R2 Std.

Zabbix shows that agent unreacheble, bet server is up and running. When I restart agent service - unreachable message diasapiers... For a couple of days..

I make fresh install of agent v3.4.1 - no luck...

In agent log i see, that agent stuck on:

 
15740:20171204:152038.171 In collect_perfstat()
 15740:20171204:152038.176 End of collect_perfstat()
 15740:20171204:152039.229 In collect_perfstat()
 15740:20171204:152039.313 End of collect_perfstat()
 15740:20171204:152040.340 In collect_perfstat()
 15740:20171204:152040.416 End of collect_perfstat()
 15740:20171204:152041.446 In collect_perfstat()
 15740:20171204:152041.449 End of collect_perfstat()
 15740:20171204:152042.532 In collect_perfstat()
 15740:20171204:152042.536 End of collect_perfstat()

Any ideas?