Please ignore my previous post, titled “Path for ISO’s on XenServer 5.5″. That was typed in such rush.

For those of you wanting to store your ISO’s on the Xen server itself and not some remote location on NFS (I find it odd how Citrix is really pushing that method to the extreme), this is what works for me:

Simply scp your ISO’s to “/var/opt/xen/iso_import” on the Xen server.
From googling around, I see most people resort to restarting their server or detach/retach the storage to have XenCenter show those newly uploaded ISO’s. If you can’t afford having it restarted, then read on…
After you uploaded your ISO’s, do:

xe sr-list

This will list all your storage devices. Look for the one that is your local storage and copy the uuid from it. Next do:

xe sr-scan uuid=YOUR_UUID_HERE

This will rescan your local storage.

Now check XenCenter and you will see your new ISO’s there ready to be used.