Cisco 6509-E going to rommon mode after restart

net buzz · ‎02-24-2016

Hi!

I am getting an issue with a Cisco 6509-E switch as it goes to rommon mode each time it is restarted.

From the rommon mode, the switch can only be booted when using the IOS from the PCMCIA card (disk0).

Following successful booting from disk0, switch goes to rommon upon reboot.

bootflash is also not available and does not contain a valid magic number.

See below output:

Testing lower main memory - data equals address
Testing lower main memory - checkerboard
Testing lower main memory - inverse checkerboard
Clearing lower 16K memory for cache initialization
Clearing bss
Clearing autoboot state machine

Reading monitor variables from NVRAM
Reset reason 0x8ffff.
Enabling interrupts
Initializing TLB
Initializing cache
Initializing required TLB entries
Initializing main memory
Sizing NVRAM
Initializing PCMCIA controller
Exiting init
Cat6k-Sup720/SP processor with 524288 Kbytes of main memory

rommon 1 > dev
Devices in device table:
        id name
bootflash: boot flash
    disk0: PCMCIA Disk 0
    disk1: PCMCIA Disk 1
    eprom: eprom
rommon 2 > dir bootflash:

Read cis from dev 1 error (-6)device does not contain a valid magic number
dir: cannot open device "bootflash:"
rommon 3 > dir disk0:
Directory of disk0:

4      80102916 -rw-     s72033-ipservicesk9_wan-mz.122-18.SXF13.bin
rommon 4 > set
PS1=rommon ! >
BSI=0
ACL_DENY=0
PF_REDUN_CRASH_COUNT=0
LOG_PREFIX_VERSION=1
RANDOM_NUM=2090119228
SLOTCACHE=cards;
RET_2_RTS=23:49:19 UTC Fri Oct 30 2015
RET_2_RCALTS=1446248958
?=0
rommon 5 > boot disk0:s72033-ipservicesk9_wan-mz.122-18.SXF13.bin
Loading image, please wait ...

After successful booting:

Router#sh bootvar
BOOT variable =
CONFIG_FILE variable =
BOOTLDR variable =
Configuration register is 0x2102

Standby is not present.

Router#remote command switch sh bootvar

BOOT variable does not exist
CONFIG_FILE variable does not exist
BOOTLDR variable does not exist
Configuration register is 0x8000

Leo Laohoo · ‎02-24-2016

Router#sh bootvar
BOOT variable =

Do this:

config t
 boot system flash disk0:
end
wr

net buzz · ‎02-26-2016

Hi Leo!

I have executed the commands as mentioned.

However after saving and reloading, the Cisco 6509 goes back to rommon mode.

Please see below output:

rommon 1 > boot disk0:s72033-ipservicesk9_wan-mz.122-18.SXF13.bin
Loading image, please wait ...

After successful booting:

Router#show bootvar
BOOT variable =
CONFIG_FILE variable =
BOOTLDR variable =
Configuration register is 0x2102

Router(config)#boot system flash disk0:s72033-ipservicesk9_wan-mz.122-18.SXF13.bin

Router#show bootvar
BOOT variable = disk0:s72033-ipservicesk9_wan-mz.122-18.SXF13.bin,1;
CONFIG_FILE variable =
BOOTLDR variable =
Configuration register is 0x2102

Router#remote command switch show bootvar

BOOT variable = disk0:s72033-ipservicesk9_wan-mz.122-18.SXF13.bin,1;
CONFIG_FILE variable does not exist
BOOTLDR variable does not exist
Configuration register is 0x8000

When rebooting, the Cisco 6509 goes back to rommon.

rommon 1 > set
PS1=rommon ! >
LOG_PREFIX_VERSION=1
SLOTCACHE=cards;
BOOT=disk0:s72033-ipservicesk9_wan-mz.122-18.SXF13.bin,1;
?=0
BSI=0
ACL_DENY=0
PF_REDUN_CRASH_COUNT=0
RANDOM_NUM=1278066608
RET_2_RTS=01:21:53 UTC Sat Oct 31 2015
RET_2_RCALTS=1446254512

Need to issue boot disk0:s72033-ipservicesk9_wan-mz.122-18.SXF13.bin for the Cisco 6509 to boot successfully.

Another observation is that when shutting down the Cisco 6509 and powering again the set command in rommon is as follows:

System Bootstrap, Version 8.1(3)
Copyright (c) 1994-2004 by cisco Systems, Inc.

Testing lower main memory - data equals address
Testing lower main memory - checkerboard
Testing lower main memory - inverse checkerboard
Clearing lower 16K memory for cache initialization
Clearing bss
Clearing autoboot state machine

Reading monitor variables from NVRAM
Warning: Rommon NVRAM area is corrupted. Initialize the area to default values

Reset reason 0xffff.
Enabling interrupts
Initializing TLB
Initializing cache
Initializing required TLB entries
Initializing main memory
Sizing NVRAM
Initializing PCMCIA controller
Exiting init
Cat6k-Sup720/SP processor with 524288 Kbytes of main memory

rommon 1 > set
PS1=rommon ! >

Iulian Vaideanu · ‎02-26-2016

The configuration register on the SP (0x8000 in your case) can be fixed by "conf t / config-register 0x2102 / wr mem" (which updates it on both SP and RP).

However, the corrupted NVRAM after power-offs is a good hint that the CR1225 3V lithium battery on the supervisor has lived its life - I've been in this situation, and replacing that battery fixed things for me.

Also happened to other people: https://supportforums.cisco.com/discussion/10513296/sup720-sp-rommon-looses-confreg-and-config-nvram-corrupted

net buzz · ‎05-25-2016

That's correct.

I replaced that CR1225 3v lithium battery and it solved the issue.

Many thanks.