Guidelines for Selecting Slices for File Systems

When you create file systems for a boot environment, the rules are identical to the rules for creating file systems for the Solaris operating environment. Solaris Live Upgrade cannot prevent you from creating invalid configurations for critical file systems. For example, you could type a lucreate command that would create separate file systems for root (/) and /kernel—an invalid division of root (/).

Do not overlap slices when re-slicing disks. If this condition exists, the new boot environment appears to have been created, but when activated, the boot environment does not boot. The overlapping file systems might be corrupted.

For Solaris Live Upgrade to work properly, the vfstab file on the active boot environment must have valid contents and must have an entry for root (/) at the minimum.

Guidelines for Selecting a Slice for the root (/) File System

When you create an inactive boot environment, you need to identify a slice where the root (/) file system is to be copied. Use the following guidelines when you select a slice for the root (/) file system. The slice must comply with the following:

• Must be a slice from which the system can boot.

• Must meet the recommended minimum size.

• Cannot be a Veritas VxVM volume.

• Can be on different physical disks or the same disk as the active root (/) file system.

• If you have a sun4m system, the root (/) file system cannot be greater than 2 Gbytes.

The Choices menu displays most free slices that are available for the creation of an inactive boot environment. Some slices are free, but not available to be shown in the Choices menu, such as a Veritas VxVM volume or a Solaris Volume Manager metadevice.

Guidelines for Selecting Slices for root (/) Mirrors and Metadevices

You can use Solaris Live Upgrade on a system that is currently using either Solaris Volume Manager metadevices or Veritas Volume Manager VxVM volumes. The source boot environment can be contained on any combination of physical disk slices, Solaris Volume Manager metadevices, or Veritas Volume Manager volumes. When creating a new boot environment, the slice that is chosen for the root (/) file system for the new boot environment can be either a physical disk slice or a Solaris Volume Manager metadevice. If you choose a Solaris Volume Manager metadevice for the root file system, the metadevice must be either a stripe with only a single disk or a mirror on a single-disk stripe. See metaroot(1M) for more details.

You cannot use a Veritas VxFS volume for the root (/) file system when creating a new boot environment. For any file system except the root (/) file system, you can use either a physical disk slice, a Solaris Volume Manager metadevice, or a Veritas VXFS volume.

Table 31–2 describes the acceptable disk configurations for creating a boot environment when using metadevices or volumes.

Table 31-2 Acceptable Slices for Metadevices or Volumes

Product	Source Slice	If Target Is a Metadevice for a root (/) File System	If Target Is Not a root (/) File System, But Is for /usr, /var, or /opt
Solaris Volume Manger	For the root (/) file system, the source can be a metadevice or physical slice.	The root (/) file system, must be either a stripe with only a single disk or a mirror on a single-disk stripe.	Other file systems can be either a physical slice or metadevice.
Veritas VxVM Volume Manager	For the root (/) file system, the source can be a volume or physical slice.	The root (/) file system, cannot be a VxVM volume; root (/) must be a physical slice.	Other file systems can be either a physical slice or volume.

When creating a new boot environment, the lucreate -m command recognizes the following three types of devices only:

• A physical slice in the form of /dev/dsk/cnumtnumdnumsnum

• A Solaris Volume Manager metadevice in the form of /dev/md/dsk/dnum

• A Veritas VxFS volume in the form of /dev/vx/dsk/volume_name

Using boot environments with metadevices or volumes has special considerations when upgrading or installing a flash archive. See “Upgrading Metadevices and Volumes” for details.

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Note -

If you have problems upgrading with Veritas VxVM, see “System Panics When Upgrading With Solaris Live Upgrade Running Veritas VxVm”.

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Guidelines for Selecting a Slice for a swap File System

The swap slice cannot be in use by any boot environment except the current boot environment or, if the -s option is used, the source boot environment. The boot environment creation fails if the swap slice is being used by any other boot environment, whether the slice contains a swap, UFS, or any other file system.

Guidelines for Selecting Slices for Shareable File Systems

Solaris Live Upgrade copies the entire contents of a slice to the designated new boot environment slice. You might want some large file systems on that slice to be shared between boot environments rather than copied to conserve space and copying time. File systems that are critical to the operating environment such as root (/) and /var must be copied. File systems such as /home are not critical file systems and could be shared between boot environments. Shareable file systems must be user-defined file systems and on separate swap slices on both the active and new boot environments. You can reconfigure the disk several ways, depending your needs.

• You can reslice the disk before creating the new boot environment and put the shareable file system on its own slice. For example, if root (/), /var, and /home are on the same slice, reconfigure the disk and put /home on its own slice. When you create any new boot environments, /home is shared with the new boot environment by default.

• If you want to share a directory, the directory must be split off to its own slice. The directory is then a file system that can be shared with another boot environment. You can use the lucreate command with the -m option to create a new boot environment and split a directory off to its own slice. But, the new file system cannot yet be shared with the original boot environment. You need to run the lucreate command with the -m option again to create another boot environment. The two new boot environments can then share the directory.

  For example, if you wanted to upgrade from the Solaris 8 release to the Solaris 9 release and share /home, you could run the lucreate command with the -m option. You could create a Solaris 8 release with /home as a separate file system on its own slice. Then run the lucreate command with the -m option again to duplicate that boot environment. This third boot environment can then be upgraded to the Solaris 9 release. /home is shared between the Solaris 8 and Solaris 9 releases.

For a description of shareable and critical file systems, see “Creating a Boot Environment Overview”.