layout_constraint slice constraint [[minimum_size]] |
You can use layout_constraint only for the upgrade option when you need to reallocate disk space.
layout_constraint designates the constraint auto-layout has on a file system if it needs to reallocate space during an upgrade because of space problems.
If you don't specify the layout_constraint keyword, the:
File systems requiring more space for the upgrade are marked changeable
File systems on the same disk as the file system requiring more space (mounted by the /etc/vfstab file) are marked changeable
Remaining file systems are marked fixed (auto-layout can't change them)
If you specify one or more layout_constraint keywords, the:
File systems requiring more space for the upgrade are marked changeable
File systems for which you specified a layout_constraint keyword are marked with the specified constraint
Remaining file systems are marked fixed
Even though you can't change the constraint on file systems requiring more space for the upgrade (they must be marked changeable), you can use layout_constraint on those file systems to change their minimum_size values.
To help auto-layout reallocate space, select more file systems to be changeable or moveable, especially those that are located on the same disks as the file systems that require more space for the upgrade.
slice - This is the file system's disk slice on which to specify the constraint. You must specify the system's disk slice in the form cwtxdysz or cxdysz.
constraint - Choose one the following constraints for the specified file system:
changeable - Auto-layout can move the file system to another location and it can change its size. This constraint can only be specified on file systems that are mounted by the /etc/vfstab file. You can change the file system's size by specifying the minimum_size value.
When you mark a file system as changeable and minimum_size is not specified, the file system's minimum size is set to 10 percent greater than the minimum size required. For example, if the minimum size for a file system is 100 Mbytes, the changed size is 110 Mbytes. If minimum_size is specified, any free space left (original size minus minimum size) is used for other file systems.
movable - Auto-layout can move the file system to another slice (on the same disk or different disk) and its size stays the same.
available - Auto-layout can use all of the space on the file system to reallocate space. All the data in the file system is lost. This constraint can only be specified on file systems that are not mounted by the /etc/vfstab file.
collapse - Auto-layout moves (collapses) the specified file system into its parent file system. You can use this option to reduce the number of file systems on a system as part of the upgrade. For example, if a system has the /usr and /usr/openwin file systems, collapsing the /usr/openwin file system moves it into /usr (its parent). You can specify this constraint on only file systems that are mounted by the /etc/vfstab file.
minimum_size - This value specifies the size of the file system after auto-layout reallocates space. This option enables you to change the size of a file system. The size of the file system may end up being more if unallocated space is added to it, but the size is never less than the value you specify. You can use this optional value only if you have marked a file system as changeable, and the minimum size cannot be less than what the file system needs for its existing contents.
Examples:
layout_constraint c0t3d0s1 changeable 200 layout_constraint c0d0s4 movable layout_constraint c0t3d1s3 available layout_constraint c0t2d0s1 collapse