Allied Telesis Rapier Switch - Manual (Page 21)

Operating the Switch 21
Rapier Switch Software Release 2.2.1
C613-02013-00 Rev A
Install Information
The INSTALL module is responsible for maintaining install information and
loading the correct install at boot. A release is a binary file containing the code
executed by the switches CPU. There may also be a patch file, and additional
binary file that modifies the original release file. An install is a record
identifying a release and an optional patch. Three installs are maintained by
the INSTALL module, temporary, preferred and default.
The default install is the install of last resort. The release for the default install
can not be changed by the manager and is always the EPROM release. The
patch for the default install may be set by the manager.
The temporary and preferred installs are completely configurable. Both the
release and an associated patch may be set. The release may be EPROM or a
release stored in FLASH.
The three different installs are required to handle the following situations:
■ A default install is required to handle the case when only the EPROM
release is present.
■ A temporary install is required to allow a release and/or patch to be
loaded once only, in case it causes a switch crash.
■ A preferred install is required because the default install can not be
anything other than the EPROM.
The install information is inspected in a strict order. The temporary install is
inspected first. If this install information is present, the temporary install is
loaded. At the same time, the temporary install information is deleted. This
ensures that if the switch reboots immediately as the result of a fatal condition
caused by the temporary install, the temporary install will not be loaded a
second time.
If there is no temporary install defined, or the install information is invalid, the
preferred install is inspected. If present, this install is loaded. The preferred
install information is never deleted.
If neither temporary nor preferred installs are present, the default install is
used. The default install will always be present in the switch, because if, for
some reason, it is not, the INSTALL module will restore it.
The preferred install should not be set up with an untested release or patch. It
is advisable to install new releases or patches as the temporary install, and
when the switch boots correctly, to then set up the preferred install with the
new release or patch.
To change the install information in the switch, use the command:
SET INSTALL={TEMPORARY|PREFERRED|DEFAULT}
[RELEASE={release-name|EPROM}] [PATCH[=patch-name]]
The INSTALL parameter specifies which install is to be set. The INSTALL
module is responsible for maintaining install information and loading the
correct install at boot. An install is a record identifying a release and an optional
patch. Three installs are maintained by the INSTALL module, temporary,
preferred and default.