29.2 Cannot Create an NSS Pool or Volume

If you cannot create an NSS pool or volume, consider these possible causes:

29.2.1 General Issues

  • Your server might not have enough free space to create more storage pools or NSS volumes. Ensure you have enough free space to create another NSS storage pool or NSS volume. See Section 10.8, Viewing Partitions on a Device.

  • Each NSS volume must be part of an NSS pool. If you cannot create the pool at the same time as the volume, try creating a pool to use first.

29.2.2 Linux Issues

If you cannot create a pool on a device you can see in NSSMU, NSS might not own the free space you want to use for a storage pool. If the device you want to use is managed by LVM2 instead of EVMs, NSS does not recognize the device as being available and does not create the pool.

SUSE Linux Enterprise Server uses LVM2 as the default device manager, but NSS requires EVMS. The Linux 2.6 kernel prevents multiple volume managers from managing the same device. As a result, EVMS might display free space that it cannot actually manage.

To prevent display of space that is unavailable to EVMS, edit the /etc/evms.conf file to add the device to the exclude list of the sysfs_devices section.

For example, if your hda device is your boot device and contains the root volume, it cannot be used to create pools on. Edit the /etc/evms.conf file as follows:

sysfs_devices {
exclude = [hda]

To make a device that is being managed by another device manager available to EVMS, you can use one of the following options:

  • Install Linux with EVMS as the default volume manager

    See Mounting Your Root File System through EVMS for more information.

  • Convert LVM2 volumes to EVMS volumes after Linux installation.

    See Converting to EVMS for more information.

  • Patch the 2.6 kernel on your Linux server to allow multiple device managers.

    WARNING:This solution is not recommended, tested, nor supported, but it is mentioned here for completeness.

    See BD-Claim Patch for more information.