Dear Team,

I have one master node and child node, their version is 2.0.8. After upgrade the 2.0.8 to 2.2.2, having below issues in server.

Issue:

1. Getting below error's in Master node /tmp/zabbix_server.log file
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14688:20140730:172650.120 [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
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