ZFS Flash Support

ZFS Flash Support

ZFS Flash archive support is available in the Solaris 10 10/09 release. It is not currently supported in the Nevada release or the OpenSolaris release.

Patch Information

You can install the following patches to create a ZFS Flash archive on a Solaris 10 10/08 system or Solaris 10 5/09 system:

• Solaris 10 5/09 - The flarcreate and flar patches (119534-15/119535-15) must be applied to the system where the Flash archive is created. The install software patch (124630-26/124631-27) must be applied to the install medium (probably a net install image), since that is where the installation software resides. A system being installed with a Flash archive image has to be booted from a patched image so that the installation software can recognize a ZFS Flash archive and handle it correctly.
• Solaris 10 10/08 - In addition to applying the flarcreate and flar patches (119534-15/119535-15), the install software patch (124630-26/124631-27) must be applied to the install medium (probably a netinstall image) and the kernel update (KU) patch must be applied to the net install image for the installation to succeed. The KU patch is 139555-07 (or later) for SPARC and 139555-07 (or later) for x86.

Important Notes

• The kernel patch level of the system on which the ZFS flash archive is created must be equal to or greater than the kernel patch level of the install image. For example, you cannot create a ZFS flash archive on a system that is running a Solaris 10 5/09 kernel and install it with a Solaris 10 10/09 install image. The ZFS storage pool that is created by the install software running on a Solaris 10 10/09 system will have an on-disk format that cannot be read by the Solaris 10 5/09 kernel in the ZFS flash archive. The install will complete correctly, but the system will not boot because the kernel installed from the Solaris 10 5/09 flash archive won't be able to read the pool in which it is installed.
• An entire ZFS root pool is archived with flarcreate and only the ZFS BE that is booted when the archive is created is usable after the Flash archive is installed. Consider removing unnecessary BEs and snapshots that are unrelated to the active BE before creating a ZFS Flash archive.

Feature Description

• A Flash archive can be created on a system that is running a UFS root file system or a ZFS root file system.
• A Flash archive of a ZFS root pool can be installed in the following ways:
  • JumpStart installation of the ZFS flash archive in a local area network
  • JumpStart installation of the ZFS flash archive in a wide area network utilizing the WAN boot feature
• A Flash archive of a ZFS root pool contains the entire pool hierarchy, except for the swap and dump volumes, and any excluded datasets. The swap and dump volumes are created when the Flash archive is installed. If you create Flash archive of a ZFS root pool that will be installed by using the WAN boot method, the size of Flash archive will be equivalent to the size of the ZFS root pool. Consider removing unnecessary data before creating the Flash archive of the root pool if you will be installing the ZFS Flash archive with WAN boot.
• You can use the Flash archive installation method as follows:
  • Generate a Flash archive that can be used to install and boot a system with a ZFS root file system.
  • Perform a JumpStart installation of a system by using a ZFS Flash archive. Creating a ZFS Flash archive clones an entire root pool, not individual boot environments. Individual datasets within the pool can be excluded using the flarcreate and flar command's -D option.

Limitations

Review the following limitations before you consider installing a system with a ZFS Flash archive:

• Only a JumpStart installation of a ZFS Flash archive is supported. You cannot use the interactive installation option of a Flash archive to install a system with a ZFS root file system. Nor can you use a Flash archive to install a ZFS BE with Solaris Live Upgrade.
• You can only install a system of the same architecture with a ZFS Flash archive. For example, an archive that is created on a  sun4u system cannot be installed on a sun4v system.
• Only a full initial installation of a ZFS Flash archive is supported. You cannot install differential Flash archive of a ZFS root file system nor can you install a hybrid UFS/ZFS archive.
• Existing UFS Flash archives can still only be used to install a UFS root file system. The ZFS Flash archive can only be used to install a ZFS root file system.
• Although the entire root pool, minus any explicitly excluded datasets, is archived and installed, only the ZFS BE that is booted when the archive is created is usable after the Flash archive is installed. However, pools that are archived with the flarcreate or flar command's -R rootdir option can be used to archive a root pool other than the one that is currently booted.
• Zones configurations are not supported in a ZFS flash archive.
• A ZFS root pool name that is created with a Flash archive must match the master root pool name. The root pool name that is used to create the Flash archive is the name that is assigned to the new pool created. Changing the pool name is not supported.
• The flarcreate and flar command options to include and exclude individual files are not supported in a ZFS Flash archive. You can only exclude entire datasets from a ZFS Flash archive.
• The flar info command is not supported for a ZFS Flash archive.
• The /var directory in the root pool must be a single dataset. You cannot create and install a ZFS Flash archive that contains multiple /var datasets.

Process

• Install the flash/install-related patches on the master system. Add whatever customizations you want to it. By default, ALL datasets in the root pool (except for swap and dump) are included in the flash archive.
• Create the ZFS Flash archive with the flarcreate command on the master system. You can use the -D  option (repeatedly, if you wish) on the command line to exclude datasets from the archive. For example:

# flarcreate -n zfsu8 -D rpool/data /remote-directory/zfsu8.flar

• Create a JumpStart profile to include the flash archive information on the installation server. For example:

install_type flash_install
archive_location nfs schubert:/export/home/lalt/zfsu8.flar
partitioning explicit
pool rpool auto auto auto mirror c0t1d0s0 c0t0d0s0

• Install the ZFS Flash archive on the target system.

Feature Description Details

• Either of the following JumpStart profile keywords must be included as a long-time Flash requirement:
  • partitioning explicit
  • partitioning existing
• These keywords are somewhat unusual in a ZFS root pool environment, where only one dataset is created in the root pool and the entire disk is generally allocated to slice 0.