Migrating zabbix from 4.2 to 6.2

[balaji]

I am currently working on moving physical zabbix server 4.2 version(that is running on Centos 7) to a Zabbix 6.2 ( that is running on a Ubuntu 20.04 (focal)). The 4.2 version is using mariadb and the 6.2 version is using mysql. The size of the old server is above 2 GB. Can someone help with the steps that is should follow.

[cyber]

Shortly... export old DB, import it to new DB, start your new server, wait until upgrade procedures are done... Use it.

[balaji]

Thank you, I wanted to know whether the servers can be switched on during the migration or should i switch off the servers

[LenR]

The software requirements for 6.2 are likely not met by your 4.2 host, you will need to migrate to a new host. Here's how I've done it in the past.

1. Check mysql upgrade path. Mysql doc says you can only upgrade one version at a time, so see what steps are needed between your systems. If it's only 1, you're good. If not, upgrade mysql in place (after backups!) until you get to a 1 step upgrade. IIRC, I had to do a mysql 5.5 > 5.6 > 5.7 on my old system, then the 5.7 > 8.0 happened on the new system.
2. I've always done like systems, RHEL to RHEL, so you need to test this step; with mysql stopped on both systems, use rsync to copy the entire /var/lib/mysql directory from old to new. When you start mysql on the new server, for 8.0 equivalents, it should do an automatic upgrade (This is NOT the zabbix db upgrade!)
3. Start the zabbix server on the new host, it should show in the log where it goes thru the zabbix db upgrade.
4. Follow the steps for DB charset and adding index to history (optional)

Since you really aren't changing your old system, you can repeat this process until it works.