System information

Operation 1-35
Software Release 2.0.1
C613-03018-00 REV A
A software release is specific to a particular router series. It is not possible to
run a release on any router series other than that for which the release was
made. The same router release will, however, run on all models in the same
series. If an attempt is made to load the wrong software release into the router
the boot process will fail.
Patches
A router patch contains changes to the router software. A patch usually
contains fixes to software errors, although enhancements to the software may
sometimes be released as patches. Patches are identified by names like
“7.6.0-2”. In this case, “7.6.0” is the release that the patch modifies, and “2” is a
version number that identifies the patch in a series (1, 2, 3...) of patches. Patches
are specific to a particular release, and thus to a particular router series. Any
attempt to use a patch with a non-matching release will result in failure.
A standard patch is a single file with a name of the form:
mmrrr-pp.PAT
where
mm
identifies the router model (Table 1-7 on page 1-34),
rrr
is the release
number (e.g.
761
for Software Release 7.6.1), and
pp
is the version number of
the patch.
Compressed patches are supported on routers running a base EPROM release
of Software Release 7.4 or later. The patch consists of a single file:
mmrrr-pp.PAZ
Compressed patches are not supported for routers running base EPROMs prior
to Software Release 7.4 and running a compressed release.
Patches may be loaded into either FLASH, or, if the patch is small enough, into
NVS. There is no difference between a patch file loaded into FLASH and a patch
file loaded into NVS; the difference lies in the command used to load the file.
The INSTALL information that specifies the release to use also contains
information about the patch. It is possible to load a router with a number of
different patches, but only one patch can be run at a time.
Router Startup Operations
When the router boots, the following sequence of operations is performed:
1. Perform startup self tests.
2. Perform the install override option.
3. Load the EPROM release as the INSTALL boot.
4. Inspect and check INSTALL information.
5. Load the required EPROM or FLASH release as the main boot.
6. Start the router.
7. Execute the boot script, if one has been configured.