Creating a new boot environment entails copying critical file systems to another slice. The disk might need to be prepared before you create the new boot environment. Check the disk to make sure it is formatted properly:
Identify slices large enough to hold the file systems to be copied.
Identify file systems that contain directories that you want to share between boot environments rather than copy. If you want a directory to be shared, you need to create a new boot environment with the directory put on its own slice. The directory is then a file system and can be shared with future boot environments. For more information on creating separate file systems for sharing, see Guidelines for Selecting Slices for Shareable File Systems.
The process of creating a new boot environment begins by identifying an unused slice where the critical file systems can be copied. If a slice is not available or a slice does not meet the minimum requirements, you need to format a new slice. For the procedure on formatting a slice from menus, see “To Create a Boot Environment (Character Interface)” Step 6.
After the slice is defined, you can reconfigure the file systems on the new boot environment before the file systems are copied into the directories. You reconfigure file systems by splitting and merging them, which provides a simple way of editing the vfstab to connect and disconnect file system directories. You can merge file systems into their parent directories by specifying the same mount point, or you can split file systems from their parent directories by specifying different mount points.
For procedures on splitting and merging file systems, see the following procedures:
After file systems are configured on the inactive boot environment, you begin the automatic copy. Critical file systems are copied to the designated directories. Shareable file systems are not copied, but are shared. The exception is that you can designate some file systems to be copied. When the file systems are copied from the active to the inactive boot environment, the files are directed to the newly defined directories. The active boot environment is not changed in any way. For procedures on creating a new boot environment, see Creating a New Boot Environment.
The following figures illustrate various ways of creating new boot environments.
Figure 30–1 shows the critical file system root (/) that has been copied to another slice on a disk to create a new boot environment. The active boot environment contains root (/) on one slice. The new boot environment is an exact duplicate with root (/) on a new slice. The file systems /swap and /export/home are shared by the active and inactive boot environments.
Figure 30–2 shows critical file systems that have been split and been copied to slices on a disk to create a new boot environment. The active boot environment contains root (/) on one slice. On that slice, root (/) contains the /usr, /var, and /opt directories. In the new boot environment, root (/) is split and /usr and /opt are put on separate slices. The file systems /swap and /export/home are shared by both boot environments.
Figure 30–3 shows critical file systems that have been merged and been copied to slices on a disk to create a new boot environment. The active boot environment contains root (/), /usr, /var, and /opt each on their own slice. In the new boot environment, /usr and /opt are merged into root (/) on one slice. The file systems /swap and /export/home are shared by both boot environments.