It's difficult to say. Could you give us some more information about what type of SAN you are using and how it is configured. That is: SAN network layout, Disk layout, How is the data distributed over the disks.
Otherwise I have to guess and my conclusion would be not possible.
Reason for this: If System A has to run Apache/zabbix and System B Mysql in a failover situation they need both access to the same disks on the SAN. Which is not possible in normal failover configurations. Unless you got special software that allows this.
Besides I didn't know that configuring and maintaining HA clusters is a newbie job nowadays.