SNMP agent item "....[540]" on host "xxxx" failed: first network error, wait for 15

[metal]

Actually, I solved that error, at least in my case, I was using vmware workstation, and I noticed that there was a drop in the network on that VM, so I converted it into ESXi, and the problem disappeared. So it is not a zabbix issue, rather a network card issue.

[adaker]

I am running v4.4.5 on Debian 10 in a ESX virtual machine. I am experiencing the exact same symptoms. To rule out a resource issue, I disabled all but one host and ran tests. I receive network errors on randomly on different OIDs. Packet captures show that the SNMP response is received, however Zabbix produces the network error like it never saw the response.