Sorry for not complete description:
Steps to reproduce:
 1. run server process more the 3 Days without restart
Result:
 Serverprocess runs into error and restarts somtime or not
Expected:
 no errors, no restarts

The current installation is upgraded from 2.x over 3,4,5 and 6.0tls to 7.03 over years.
In Logfile an objectdump is requested. Both Errorlog and objectdump are attached.

System Configuration:
Debian 12 amd64 (bookworm)
mariadb 11.3.22
snmp/stable,now 5.9.3+dfsg-2 amd64
No proxy, no HA

Please provide version and arch of OS + version of installed net-snmp.

actualisation System configuration

How often such issue happens? Looks like crash happened in net-snmp. Is it possible to increase debug level and wait next crash? Like this:

zabbix_server -R log_level_increase="discovery manager"

Server new start with reqested LogLevel. Waiting for error.

Stops working after ~3h
Log with 
zabbix_server -R log_level_increase="discovery manager"
attached: zabbix_server.log.7z

Sorry, but there is no one crash, everything looks like. Maybe the crash was before 833072:20240903:071856.520?

Not that was the time off restart zabbix service.
I'll do a next try, starting at 03.Sep.2024 ~12:47

Ah... so, looks like the log file was rewritten... there is no any information about crash. Please try again.

Now ist runs over 8 days (since 3.Sep 12:45) without Problems with increased loglevel.

Stop working tonight. Logfile and Dump are in zabbixbug_ZBX-25146-09-09-2024.7z:
systemctl stop zabbix-server.service wont work.
I will let it as it is, may be for debugging until 12:00 today.

Now an error occures after two days.
only Logfile without increased loglevel in zabbixbug_ZBX-25146-23-09-2024.7z

twao restart since yesterday zabbixbug_ZBX-25146-24-09-2024.7z

Thank you! What SNMP discovery version do you use? How many SNMP discovery checks do you have?
Is it possible to specify "999" concurrent checks for all SNMP discoveries?

Where do I find the SNMP discovery version? snmp tools is stable 5.9.3.
I've attached my cleanup zabbix_server.conf which was modified on base of defaut after upgrade to version 7.0 from 6.0 LTS which wont work correctly. Currently I have also trouble with my backups, so I can't get the last working version for 6.0 from there.

You find SNMP prototocl version directly in network discovery (v1, v2 or v3).

Under 'Data Collection' | 'Discovery' I have 4 Items one with ICMP Ping only and 3 with ICMP Ping, SNMPv1 agent, SNMPv2 agent, Zabbix agent. All Items with SNMP Agent have different IP-Ranges, no overlaping, and they have set 'Maximum concurrent checks per type' to one.
Is this the place where to take 'custom' with '999'?

Is this the place where to take 'custom' with '999'?

Yes, please.

SNMPv1 agent

Any reasons to use SNMP v1?

I will change it to 999 and deactivate snmp v1

These changes do it right, no more stops.
This solves the Problem. But a more detailed hint in the Logfile is needed.

Available in:

• 7.0.12rc1 267b67a4164
• 7.2.6rc1 0dc93e2a287,  d5c9d624991
• 7.4.0beta1(master) 250bd54ca71,  0ecfc917d11