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Parallels Virtuozzo Containers for Linux supports placing the /vz partition over NFS, but it is necessary to remember the product peculiarities while choosing an NFS storage solution. There were several issues discovered with third-party NFS solutions:

  1. Veritas Storage Foundation Cluster File System by Symantec does not support creating devices on its volumes: Veritas Storage Foundation Cluster File System High Availability Administrator's Guide, page 48:

    The "mknod" command cannot be used to create devices on a cluster-mounted file system.

    Therefore, it is impossible to place a container's private area on such volumes.

  2. BlueArc Silicon FS by BlueArc generates 64-bit inode numbers, which may result in various issues for Parallels Virtuozzo Containers for Linux if it has a 32-bit kernel. 64-bit kernels work fine with 64-bit storage.

  3. NFS Server by Microsoft generates non-unique cookies for files in a single directory scope, which leads to a kernel loop and "freezing" for userspace tools, according to Trond Myklebust. A typical example is a hanging vzpkg create cache command.

General recommendations for placing /vz on NFS share

  • Preserve architecture: Put 64-bit systems onto 64-bit NFS servers and 32-bit systems onto 32-bit NFS servers

  • Do not separate /vz: 32-bit systems cannot host /vz on an NFS share if templates and CT private areas are located on different NFS volumes

  • Verify device support: Make sure that the NFS share supports hosting Unix devices (mknod)

Also see

111855 /vz over NFS: online migration does not work

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