Dear Team,

I have upgrade the Master node and child node from 2.0.8 to 2.2.5, after upgrade i have faced the below issue.

Getting below error in Master node /tmp/zabbix_server.log file

Error:
----------
14694:20140730:173154.662 [Z3005] query failed: [1452] Cannot add or update a child row: a foreign key constraint fails (`zabbix`.`alerts`, CONSTRAINT `c_alerts_2` FOREIGN KEY (`eventid`) REFERENCES `events` (`eventid`) ON DELETE CASCADE) [insert into alerts (alertid,actionid,eventid,userid,clock,mediatypeid,sendto,subject,message,status,retries,error,esc_step,alerttype) values (200000000000002,200200000000003,200000000000853,200200000000001,1406367542,NULL,'','PROBLEM: Zabbix agent on childnode is unreachable for 5 minutes','Trigger: Zabbix agent on childnode is unreachable for 5 minutes
---------

Getting below error in Child node /tmp/zabbix_server.log file

Error:
-------------
3323:20140726:153321.726 NOT OK
3323:20140726:153331.732 NODE 2: sending alerts of node 2 to node 1 datalen 906
3323:20140726:153331.765 NOT OK
3323:20140726:153331.765 NODE 2: sending history_sync of node 2 to node 1 datalen 333
3323:20140726:153331.798 NODE 2: sending events of node 2 to node 1 datalen 17925
3323:20140726:153331.799 NOT OK
3323:20140726:153341.806 NODE 2: sending alerts of node 2 to node 1 datalen 906
3323:20140726:153341.840 NOT OK
-----------

Best regards,
Md. Mansoor