host and storage groups on VNX

Hello,

Sorry for the newbieness of this question but I am somewhat new to this level of storage.

I have taken over a VNX5300.

It was managed by someone else in the past an is not optimally configured for our VMware environment as the person that managed it didn't seem to know much about VMware.

Basically it is fairly simple, there are two VMware groups of hosts, called clusters, however they are not actual custers, they just called them that.  They have not been joined to DRS clusters.

There are two hosts in one "cluster" and three hosts in the other "cluster"

the hosts in one cluster are joined to one unisphere storage group and the hosts in the other are joined to a second storage group.

I am redesigning and adding more hosts to the vSphere environment.  I am going to be retiring the oldest hosts and adding new hosts and joining all of them to a DRS cluster and then using resource pools to manage what happens under that... as it should be.

I am trying to do this with no downtime.

I want all hosts to be able to see all of the storage as it is all ESXi and I need this to make the DRS cluster work properly.

It appears that it is not advised to have two storage groups assigned to one LUN.

What is the best way to do this? Can I add hosts to more than one storage group?   so I could add all the hosts from one of the current storage groups to the other group, so one of the current groups contains all hosts, and then they could all see the same storage and I could remove the second storage group as it is no longer needed?  Can I do that without any interruption to service?

I can probably arrange an outage time to do this if it is necessary, but it means waiting until the weekend and delaying the redesign.

Appreciate any advice on if this will work, or any better way of doing it.

Thanks

Bill