PSK configuration - gnutls_handshake() timed out

[tlacroix]

Good morning,

I have started to configure PSK communication between my Zabbix server and its clients

For a few of them, my Zabbix server log is flooded with

zbx_tls_accept() gnutls_handshake() returned: -110 The TLS connection was non-properly terminated.
failed to accept an incoming connection: from x.x.x.x: zbx_tls_accept(): gnutls_handshake() failed: -110 The TLS connection was non-properly terminated.

Client side log

active check data upload to [zabbix:10051] started to fail ([connect] TCP successful, cannot establish TLS to [[zabbix]:10051]: gnutls_handshake() timed out)
active check data upload to [zabbix:10051] is working again

Consequence:
1- lot of logs
2- from times to times, "Zabbix agent on xxx is unreachable for 5min" (will disappear as soon as connection is working again, which usually happends 15/20s after the timeout)

I have seen there's a (quite) version mismatch between clients (4.4.x and even 3.2.x) version and server (5.4.6) - i'll start with this upgrade to see if problem comes from here
I'll also check if DNS queries could be the reason (latency when my client tries to resolve hostname "zabbix" that could explain the timeout ?)

Any other think to check ?

Thanks!

[tlacroix]

Edit : after a full hour of logs, that alert only concerned hosts with a specific template
In that template, a few items were set as "Zabbix agent (Active)" - after changing them to "Zabbix agent", it seems the TLS error is gone

to be continued

[tuxick]

In my case increasing StartAgentPollers in server config fixed it.

[tuxick]

OK, that was temporarily.