User Manual

Recovery from BTS Router Boot to ROMmon
I-56 1X SC4812T–MC BTS Optimization/ATP 5/21/04
DRAFT
ROM monitor boot conditions – Under certain circumstances the BTS
router will initialize with the ROM monitor (ROMmon) operating
system rather than the IOS. These circumstances include:
S The hexadecimal value in the router’s configuration register has been
changed from the factory default (can change the location from where
the router attempts to load code for boot–up).
S IOS file is missing from the CF memory card
S IOS file is not the first file on the CF memory card
S Startup–config file contains an outdated boot system line specifying
an IOS file which has been replaced with an updated version
S Startup–config file contains boot system line with typographical
error(s) in the IOS filename
S IOS file image on the CF memory card is corrupted
Description – Router operation on ROMmon is signalled by the display
of the
rommon # > prompt, where # is a number which increments
each time a command is issued. ROMmon is a low–level operating
system which provides limited capabilities for router testing and
troubleshooting operations, including viewing directory contents and
booting from a specified file.
Recovery methods – Two recovery methods are included in this section.
The first is the simplest and requires that a valid, uncorrupted IOS
version is installed on the CF memory card. The second method requires
additional equipment and must be used in instances such as when an IOS
file is not installed on the CF memory card or the installed IOS image is
corrupted.
Simple Recovery from Boot to
ROMmon
Requirements – Unless it is certain that the IOS image on the CF
memory card is corrupted, this method should always be the first tried
for router recovery from ROMmon initialization. This method does not
require any additional equipment beyond the items necessary to load
canned configuration files into the BTS router. To be effective, this
method does require that a valid, uncorrupted IOS image file is installed
on the router’s CF memory card.
Recovery – Follow the procedure in Table I-10 to attempt a simple
recovery from a BTS router ROMmon initialization.
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