Zabbix Agent Unreachable

[rohanp]

Hi Guys,

I have been having Zabbix Agent Unreachable issue on one of the server over past few weeks. I get one Zabbix Agent Unreachable message every day.

When the first email is received, it reads as PROBLEM in subject line but the body message says agent ping is UP. And after 5 minutes I receive another email with OK in subject line and the body message says agent ping is UP.

Below are the example emails,

PROBLEM: Zabbix agent on Zabbix.Host is unreachable for 5 minutes - Event ID 7876930

Trigger: Zabbix agent on Zabbix.Host is unreachable for 5 minutes Trigger status: PROBLEM Trigger severity: Average Trigger URL:

Item values:

1. Agent ping (Zabbix.Host:192.168.xxx.xxx:agent.ping): Up (1) 2. *UNKNOWN* (*UNKNOWN*:*UNKNOWN*:*UNKNOWN*): *UNKNOWN* 3. *UNKNOWN* (*UNKNOWN*:*UNKNOWN*:*UNKNOWN*): *UNKNOWN*

Original event ID: 7876930

----------------------------------------------------------------------------------

OK: Zabbix agent on Zabbix.Host is unreachable for 5 minutes - Event ID 7876930

Trigger: Zabbix agent on Zabbix.Host is unreachable for 5 minutes Trigger status: OK Trigger severity: Average Trigger URL:

Item values:

1. Agent ping (Zabbix.Host:192.168.xxx.xxx:agent.ping): Up (1) 2. *UNKNOWN* (*UNKNOWN*:*UNKNOWN*:*UNKNOWN*): *UNKNOWN* 3. *UNKNOWN* (*UNKNOWN*:*UNKNOWN*:*UNKNOWN*): *UNKNOWN*

Original event ID: 7876930

------------------------------------------------------------------------------------

Below is the messages from Zabbix Server Log,

Line 87705: 1711:20170810:004713.203 Zabbix agent item "net.if.out[Intel(R) 82574L Gigabit Network Connection]" on host "absxxxx004" failed: first network error, wait for 15 seconds
Line 87714: 1713:20170810:004731.782 resuming Zabbix agent checks on host "absxxxx004": connection restored
Line 88865: 1712:20170810:015746.818 Zabbix agent item "net.if.in[Intel(R) 82574L Gigabit Network Connection #2-Epfw NDIS LightWeight Filter-0000]" on host "absxxxx004" failed: first network error, wait for 15 seconds
Line 88870: 1713:20170810:015817.367 resuming Zabbix agent checks on host "absxxxx004": connection restored
Line 89049: 1709:20170810:021105.199 Zabbix agent item "net.if.in[Microsoft ISATAP Adapter #2]" on host "abswxxxx004" failed: first network error, wait for 15 seconds
Line 89096: 1713:20170810:021131.906 Zabbix agent item "net.if.out[Intel(R) 82574L Gigabit Network Connection #2-QoS Packet Scheduler-0000]" on host "absxxxx004" failed: another network error, wait for 15 seconds
Line 89099: 1713:20170810:021156.002 temporarily disabling Zabbix agent checks on host "absxxxx004": host unavailable
Line 89211: 1713:20170810:022103.872 enabling Zabbix agent checks on host "absxxxx004": host became available

-------------------------------------------------------------------------------------

Any ideas how to sort this please?

Thanks.

[rohanp]

versions

To add,

I am running Zabbix 3.0.5 on CentOS and the Zabbix Host which is having issues is running Windows 7.

[allexpetrov]

Hi, rohanp!

It looks like you agent isn't pingable, sorry for being Captain Obvious! It's looks like your netowrk is flapping, need to make sure that connection is stable.

What I want to sugest you is to do some troubleshooting steps:
1. Install Wireshark on W7 machine and launch it in background
2. Using Zabbix you can ping that host using Simple Check with icmpping key + you can also to look on percentage lost icmp packages by configuring another Simple Check with icmppingloss key ( https://www.zabbix.com/documentation.../simple_checks )
3. After error appears - go through the Wireshark dump.

Regards,
Alex