Managing Systems and Workgroups: A Guide for HP-UX System Administrators

Configuring a System
Reconfiguring the Kernel (HP-UX 11i Version 2)
Chapter 3360
Primary Swap Device
Each kernel configuration is allowed to have a primary swap device
specification. In essence, this specifies which disk volume should be used
by the system for paging. At present, only the primary swap device is
specified using the kernel configuration mechanisms; other swap devices,
if desired, are configured after boot using the swapon command or system
call, or through entries in /etc/fstab. (See swapon (1M), swapon (2),
and fstab (4) for details.)
The primary swap device is specified in a system file as a line with one of
the following forms:
swap deviceID
1
swap lvol
swap none
swap default
Only one such line is allowed. If no such line is specified, swap default
is assumed.
The first form explicitly identifies the disk device to use for paging. The
disk device must not contain a file system, and must not be an LVM or
VxVM physical volume. Disks are presently identified using hardware
paths (see ioscan (1M) for details), but this may change in future HP-UX
releases.
The second form (swap lvol) specifies that the primary swap device is
one of the logical volumes in the root LVM volume group, and that the
lvlnboot command has been used to identify the logical volume. See
lvlnboot (1M).
The third form (swap none) specifies that there should be no primary
swap device. The system will be unable to perform paging activities.
The fourth form (swap default) specifies the default behavior. It is
equivalent to lvol if the system boots from an LVM volume group.
Otherwise, paging is directed to the disk containing the root file system,
in the area between the end of the file system and the end of the disk.
1. Earlier versions of HP-UX allowed the specification of a starting
offset and size of the paging area on the specified device. These
specifications are still accepted, for backward compatibility; see
system (4) for details. New installations should not use these
obsolescent features.