agent not starting and processes more than 75% busy

[vascoleiria]

Hi

I've recently moved to zabbix from 3.4 to 4.0.12
I get agent on server not running
I have these warnings:

Zabbix unreachable poller processes more than 75% busy	17h 38m 56s	No
2019-09-02 15:54:00				PROBLEM		Zabbix server	Zabbix trapper processes more than 75% busy	17h 38m 57s	No
2019-09-02 15:53:58				PROBLEM		Zabbix server	Zabbix timer processes more than 75% busy	17h 38m 59s	No
2019-09-02 15:53:56				PROBLEM		Zabbix server	Zabbix self-monitoring processes more than 75% busy	17h 39m 1s	No
2019-09-02 15:53:55				PROBLEM		Zabbix server	Zabbix proxy poller processes more than 75% busy	17h 39m 2s	No
2019-09-02 15:53:51				PROBLEM		Zabbix server	Zabbix icmp pinger processes more than 75% busy	17h 39m 6s	No
2019-09-02 15:53:50				PROBLEM		Zabbix server	Zabbix http poller processes more than 75% busy	17h 39m 7s	No
2019-09-02 15:53:48				PROBLEM		Zabbix server	Zabbix history syncer processes more than 75% busy

I've changed the zabbix_server.conf settings for each one from 1 to 10 (at 50 the server doesn't start)
This is my server log

19184:20190903:080248.985 Starting Zabbix Agent [Zabbix server]. Zabbix 4.0.12 (revision fb4010108b).
19184:20190903:080248.986 **** Enabled features ****
19184:20190903:080248.986 IPv6 support: YES
19184:20190903:080248.986 TLS support: YES
19184:20190903:080248.986 **************************
19184:20190903:080248.986 using configuration file: /etc/zabbix/zabbix_agentd.conf
19184:20190903:080248.986 agent #0 started [main process]
19189:20190903:080248.987 agent #4 started[listener #3]
19190:20190903:080248.989 agent #5 started [active checks #1]
19188:20190903:080248.991 agent #3 started[listener #2]
19187:20190903:080248.997 agent #2 started[listener #1]
19186:20190903:080248.999 agent #1 started [collector]
19190:20190903:080251.991 active check configuration update from [127.0.0.1:10051] started to fail (ZBX_TCP_READ() timed out)
19190:20190903:080352.000 active check configuration update from [127.0.0.1:10051] is working again
19184:20190903:082516.906 Got signal [signal:15(SIGTERM),sender_pid:21556,sender_uid:0,r eason:0]. Exiting ...
19184:20190903:082516.914 Zabbix Agent stopped. Zabbix 4.0.12 (revision fb4010108b).
21572:20190903:082516.944 Starting Zabbix Agent [Zabbix server]. Zabbix 4.0.12 (revision fb4010108b).
21572:20190903:082516.944 **** Enabled features ****
21572:20190903:082516.944 IPv6 support: YES
21572:20190903:082516.944 TLS support: YES
21572:20190903:082516.944 **************************
21572:20190903:082516.944 using configuration file: /etc/zabbix/zabbix_agentd.conf
21572:20190903:082516.969 agent #0 started [main process]
21579:20190903:082516.971 agent #3 started[listener #2]
21581:20190903:082516.971 agent #5 started [active checks #1]
21578:20190903:082516.973 agent #2 started[listener #1]
21580:20190903:082516.974 agent #4 started[listener #3]
21577:20190903:082516.976 agent #1 started [collector]
21581:20190903:082519.973 active check configuration update from [127.0.0.1:10051] started to fail (ZBX_TCP_READ() timed out)
21581:20190903:082619.988 active check configuration update from [127.0.0.1:10051] is working again

Can someone give me some hints?
Thx in advance

[vascoleiria]

I solved the problem by restoring the backup to version 3.4 until someone finds a solution.

[ingus.vilnis]

Check Zabbix Server log. You posted agent log here but that is not relevant to your problem.

Blindly changing startup values for various config settings will not help you either.