When installing a XenServer there is a question in the setup wizard which asks where to place the virtual machine files. You can choose your storage and even the remaining space on the boot disk. But where to place to ISO files then? You have to create a NFS share or SMB or whatever to accomplish that. But in a 1 host environment it handy to have it on the same host. I will explain how-to use the remaining free space on the boot disk for an ISO storage repository.