failed: first network error, wait for 15 seconds

[fsousa]

Hi everybody,

I have the Zabbix 4.4.5 installed and some times I get a lot of false positives. When I get the false positives I have this on my logs:

  6024:20200313:153058.081 SNMP agent item "net.if.status[ifOperStatus.232]" on host "sw-isp-1.domain.net" failed: first network error, wait for 15 seconds
 5887:20200313:150425.014 Zabbix agent item "net.if.in[xenbr3]" on host "xen-qa-5.srv.domain" failed: first network error, wait for 15 seconds
  6024:20200313:150425.029 Zabbix agent item "system.boottime" on host "xen-qa-2.srv.domain" failed: first network error, wait for 15 seconds
  6048:20200313:150425.072 Zabbix agent item "vfs.fs.size[/var/log,pfree]" on host "xen-qa-1.srv.domain" failed: first network error, wait for 15 seconds
  5906:20200313:150425.101 Zabbix agent item "net.if.in[vif10.2]" on host "xen-qa-6.srv.domain" failed: first network error, wait for 15 seconds
  6052:20200313:150449.791 resuming Zabbix agent checks on host "xen-qa-1.srv.domain": connection restored
  6128:20200313:150449.791 resuming Zabbix agent checks on host "xen-qa-6.srv.domain": connection restored
  6073:20200313:150449.791 resuming Zabbix agent checks on host "xen-qa-2.srv.domain": connection restored
  6094:20200313:150449.797 resuming Zabbix agent checks on host "xen-qa-5.srv.domain": connection restored

  6009:20200313:150842.939 Zabbix agent item "net.if.out[eth2]" on host "xen-qa-1.srv.domain" failed: first network error, wait for 15 seconds
  5981:20200313:150842.946 Zabbix agent item "net.if.out[vif16.0]" on host "xen-qa-5.srv.domain" failed: first network error, wait for 15 seconds
  5928:20200313:150843.096 Zabbix agent item "net.if.out[vif26.3]" on host "xen-qa-4.srv.domain" failed: first network error, wait for 15 seconds
  6129:20200313:150859.177 resuming Zabbix agent checks on host "xen-qa-5.srv.domain": connection restored
  6077:20200313:150859.177 resuming Zabbix agent checks on host "xen-qa-1.srv.domain": connection restored
  6118:20200313:150859.188 resuming Zabbix agent checks on host "xen-qa-4.srv.domain": connection restored

  5927:20200313:151413.109 Zabbix agent item "net.if.in[vif1.3]" on host "xen-qa-4.srv.domain" failed: first network error, wait for 15 seconds
  5955:20200313:151413.138 Zabbix agent item "net.if.in[vif17.3]" on host "xen-qa-5.srv.domain" failed: first network error, wait for 15 seconds
  6013:20200313:151413.156 Zabbix agent item "vfs.fs.size[/var/log,used]" on host "xen-qa-6.srv.domain" failed: first network error, wait for 15 seconds
  5929:20200313:151413.163 Zabbix agent item "net.if.out[vif28.1]" on host "xen-qa-3.srv.domain" failed: first network error, wait for 15 seconds
  6126:20200313:151428.459 resuming Zabbix agent checks on host "xen-qa-6.srv.domain": connection restored
  6055:20200313:151428.462 resuming Zabbix agent checks on host "xen-qa-4.srv.domain": connection restored
  6126:20200313:151428.468 resuming Zabbix agent checks on host "xen-qa-5.srv.domain": connection restored
  6099:20200313:151428.470 resuming Zabbix agent checks on host "xen-qa-3.srv.domain": connection restored

I don't understand what is happening ?

If you need more detailed configation, let me know...

Thank you.

[Hamardaban]

This most likely means that the server does not have time to get the requested value from the agent during the timeout period. For example due to the fact that the agent does not have time to calculate the size of files in the folder or something else. There may be problems in the network when transmitting data.... Also check the time synchronization between the agent and the server.
See what's going on in the agent's logs. Use the options to increase the debugging level

https://www.zabbix.com/documentation/current/manpages/zabbix_agentd

[bbrendon]

Did you figure this out? I have a similar issue. zabbix_get on the item key is fine but the zabbix server is freaking out. I'm getting the "failed: first network error, wait for 15 seconds" every 30 seconds or so to the same host. It's a 5.2.0 server but I'm not sure if the server version matters.

EDIT: Found the issue. increase the server timeout (passive check) and not just the agent timeout.

[lptarik]

Hello Brendon, I didn't understand the increase the server timeout (passive check) part. Are you saying below config?

### Option: Timeout
# Specifies how long we wait for agent, SNMP device or external check (in seconds).
#
# Mandatory: no
# Range: 1-30
# Default:
Timeout=30