Syncing issue with passive proxy

[SZE]

Hi

We have an issue when trying to add a new passive proxy (named passive-proxy here) to our zabbix cluster (3 zabbix server).

After adding the passive proxy correctly in Web GUI (proxy appears green Online), so communciation between server and proxy is correct.

But we have this error in the logfile of the active Zabbix server :

1287830:20260310:121306.535 cannot collect configuration data for proxy "zabbix-proxy-01": cannot get session from proxy configuration request

And simultaneously, we see this log in the logfile of the Zabbix Proxy :

1843:20260310:121045.822 cannot process proxy configuration data received from server at "<IP_of active_zabbix_server>": configuration sync is already in progress

It's like sync on the proxy nerver terminate.
And we see theses errors in loop.

Do you have any idea on what happens here ?

Thank you

[_bobby_]

I've ran into a similar problem: got

Zabbix server: More than 100 items having missing data for more than 10 minutes

error a few times on and off the last weeks.
Later I found out that it seems to stem from a specific proxy giving the same error

configuration sync is already in progress

that you mention
Restart did help but ofc only for a short time

turns out zabbix changed their config pulling interval from 1 hour to 10 seconds on version 7

I've changed that variable to 2 minutes:

ZBX_PROXYCONFIGFREQUENCY: 120

I'm not sure if thats the root of my problem or related to your problem but lets see if that works