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There is no direct correspondence between the number of virtual disks that are added to the emulated system and the number of Linux disks on which they reside. The storage on the host system just must provide enough capacity to store the disk containers used as virtual disks by the emulated system.
Please note: it is not recommended to place emulator storage devices (in particular vdisks) on NFS as this will have a significant impact on performance. However, if any of the storage (e.g., ISO files or vdisks) is on an NFS share, NFS locking must be enabled and all intermediate firewalls between client and server must allow the port used by the lockd and statd. Failure to do so will cause the emulator to hang at startup.
The sections below describe the process in more detail.
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