Zabbix Server fail

[Yauheni_Sk]

Hello everyone.

Possibly someone already faced such an issue like I had, because I didn't found any information in the log and www have to ask here.

What we have :
Separate ZBX server with 5.0.9 version
MariaDB 10.5.9 in RDS

what had happened:

1)Trappers raised up to 100%, with zabbix action logging for trappers was increased

  3638:20210728:010056.516 log level has been increased to 4 (debug)

2) about 10 minutes there such type of message

  3621:20210728:010056.516 query [txnlev:0] [update ids set nextid=nextid+1 where table_name='auditlog' and field_name='auditid']
  3637:20210728:010056.518 query [txnlev:0] [select nextid from ids where table_name='auditlog' and field_name='auditid']
  3637:20210728:010056.520 query [txnlev:0] [select nextid from ids where table_name='auditlog' and field_name='auditid']
  3637:20210728:010056.521 query without transaction detected

3) Zabbix decided to restart itself

1687:20210728:011205.202 Got signal [signal:15(SIGTERM),sender_pid:9564,sender_uid:0,re ason:0]. Exiting ...
1687:20210728:011209.325 Zabbix Server stopped. Zabbix 5.0.9 (revision 4d07aaafe2).

4) After the start some log exist and everything stopped

#freeze start
9874:20210728:011255.177 slow query: 5.576526 sec, "select clock,ns,value from history where itemid=64471699 and clock>1627391568"
9855:20210728:011255.178 slow query: 4.883012 sec, "select clock,ns,value from history where itemid=42307399 and clock>1627391569"
9838:20210728:011255.178 slow query: 5.601367 sec, "select clock,ns,value from history where itemid=57436399 and clock>1627391568"
9921:20210728:011255.178 slow query: 5.585693 sec, "select clock,ns,value from history where itemid=64331599 and clock>1627391568"
9870:20210728:011255.178 slow query: 5.595507 sec, "select clock,ns,value from history where itemid=60503299 and clock>1627391568"
9842:20210728:011255.179 slow query: 5.577535 sec, "select clock,ns,value from history where itemid=61348699 and clock>1627391568"
9926:20210728:011255.184 slow query: 4.619202 sec, "select clock,ns,value from history where itemid=13474099 and clock>1627391569"
9889:20210728:011255.196 slow query: 5.139961 sec, "select clock,ns,value from history where itemid=53557099 and clock>1627391569"

There is no data in the log then. We had to restart it manually.
Also, I found an agent failed with the error "Get value from agent failed: ZBX_TCP_READ() timed out"

Any ideas what kind of problem ut was