You can add the new server's IQN or iSCSI IP to the volume's Access Control List in advance. By default Equallogic will only allow 1 server at a time access to the volume (i.e. "Not Shared"). To change this, select the volume, go to the properties and on the advanced tab. The checkbox there is for allowing multiple servers with different IQN names (and each server should have a unique IQN name) to attach to that volume. Once you shut down or disconnect the 'old' server (and maybe wait a few seconds for the array to register the disconnect) you can connect the new server. If your servers are running VMware you can share disk access safely as the VMFS filesystem is safe to share disk access. However, do NOT allow Windows servers (NTFS) to share disk access unless those Windows servers are part of the same cluster. If you're using Linux, only certain filesystems are cluster aware (and therefor safe to share between multiple servers at the same time). If you're using XenServer, you'll want to check with Citrix what the requirements are to safely share disk access between multiple servers.
Can an EqualLogic volume be assigned to more than one Server?
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