3.2.7: Zabbix agent on HOSTNAME is unreachable for 5 minutes

[Starko]

Hello,

since we moved to Zabbix 3.2.x i have one single host that drives me mad. It's a physical Windows Server 2016 with Zabbix Agent 3.2.7. This one out of 858 hosts Triggers the Zabbix agent.ping nodata Trigger like 60-80 times a day.

I searched the Zabbix Server, Proxy and Agent Log for a clue. No hint yet.

The ICMP Echo Request never fails during that time.

Agent.ping 1hour: https://i.imgur.com/kuKTv3W.png
ICMP 1hour: https://i.imgur.com/YJFrCws.png

Any idea why a single system refuses to send data although it's available?

[allexpetrov]

Hello,

since we moved to Zabbix 3.2.x i have one single host that drives me mad. It's a physical Windows Server 2016 with Zabbix Agent 3.2.7. This one out of 858 hosts Triggers the Zabbix agent.ping nodata Trigger like 60-80 times a day.

I searched the Zabbix Server, Proxy and Agent Log for a clue. No hint yet.

The ICMP Echo Request never fails during that time.

Agent.ping 1hour: https://i.imgur.com/kuKTv3W.png
ICMP 1hour: https://i.imgur.com/YJFrCws.png

Any idea why a single system refuses to send data although it's available?

Hi there, could you please name the version of the client? But, anyway, posting a log files here could be helpful. 2 eyes - good, but 4 eyes is better

Regards,
Alex!

[Starko]

I'm so sorry that I forgot to answer you. The problem ist still existing.

Maybe some other have the same problem?

https://www.zabbix.com/forum/showthread.php?t=59605

https://www.zabbix.com/forum/showthread.php?t=57878

But regarding your questions, I already named the OS and agent version? What additional info is missing?
By now we are on Zabbix 3.2.9 on Server, Proxy and Agent.

Proxy Log: https://pastebin.com/Fr2TUN7A
Agent Log: https://pastebin.com/zHN7FfwA

[kaspars.mednis]

Hi ,

Agent.ping is a passive check from Zabbix server to Agent ?
Are other items on this host having gaps in latest data ?

i had previously similar problems with very busy windows servers flapping, maybe try to increase zabbix_agents a little in zabbix_agent conf ?

Regards
Kaspars

[Starko]

Hi, thanks four your reply!

>Agent.ping is a passive check from Zabbix server to Agent ?
Yes it is.

>Are other items on this host having gaps in latest data ?
Yes, all of them. The Proxy sets the Agent offline all the time.
Only ICMP is 100% up all the time, see my first post.

 12103:20171027:120123.709 Zabbix agent item "perf_counter[\234(_Total)\1402]" on host "WMS2016-01.domain.local" failed: first network error, wait for 15 seconds
 12107:20171027:120208.613 temporarily disabling Zabbix agent checks on host "WMS2016-01.domain.local": host unavailable

>maybe try to increase zabbix_agents a little in zabbix_agent conf ?
I already increase from 3 to 6 and then to 12. I see no difference.

[kaspars.mednis]

You have lots of messages

 4812:20171022:223657.694 the system time has been pushed back, adjusting active check schedule
  4812:20171023:043612.147 the system time has been pushed back, adjusting active check schedule
  4812:20171024:120043.153 the system time has been pushed back, adjusting active check schedule
  4812:20171026:030038.407 the system time has been pushed back, adjusting active check schedule
  4812:20171026:143224.411 the system time has been pushed back, adjusting active check schedule

i have found a potential similar problem on the zabbix russian forum

https://www.zabbix.com/forum/showthread.php?t=58199

there was an issue with hyperv hypervisor synchronizing time on hosted machine

are this error message present on another "normal" servers ?

Regards,
Kaspars

[Starko]

I think there might have been a small NTP issue, but this machine is no VM. And we don't use Hyper-V at all ;-) And we don't use active checks.

[Starko]

As you can see in my first post, the ICMP Echo Request never fails during the periods the agent is unavailable. The Agent ist passive, not active.

[Semiadmin]

Hi, Starko.
I have the same problem with several Linux servers. And I can see correlation between agent ping and tcp retransmits/s. ICMP ping ok in both directions.

[Starko]

Is this a Linux or Windows host?
Can you tell me how you configured the item?