Catalyst 6504-E going to ROMMON everytime

Answered Question
Aug 13th, 2008
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I am having conf-reg 0x2102

My image is in sup-bootflash

I used command

boot system flash sup-bootflash:xxxxx.bin

It was working properly.I tried to upgrade with new image.That's when it started giving problem.

It did not boot with new image, but rather it went to rommon.

From rommon if i use

boot bootdisk:xxxxxx.bin

it boots with the new image.

I have verified check sum of both image using verify command, it is OK.

Now it is not booting with the old image also, everytime it reload, it goes to rommon.There i use boot command and then it boots up.

Now i have deleted the new image.So only one image is there in sup-bootflash:

But still this problem is there.

Sup Engine is : VS-S720-10G



This is what file system looks like.

switch#sh file systems

File Systems:

Size(b) Free(b) Type Flags Prefixes

- - opaque ro flexwan-fpd:

- - opaque rw system:

- - opaque rw tmpsys:

- - disk rw disk0:

* 1024065536 864796672 disk rw sup-bootdisk: sup-bootflash:#

38499702 0 opaque ro sup-microcode:

0 754333620 opaque wo sup-image:

129004 128388 nvram rw const_nvram:

1964024 1952725 nvram rw nvram:

- - opaque rw null:

- - opaque ro tar:

- - network rw tftp:

- - opaque wo syslog:

65536000 65536000 flash rw bootflash:

- - network rw rcp:

- - network rw http:

- - network rw ftp:

- - opaque ro cns:

15990784 15990784 flash rw dfc#4-bootflash:

15990784 15990784 flash rw dfc#3-bootflash:

has anybody faced such a problem. ??

Correct Answer by Johann Frey about 8 years 10 months ago

look for the conf-reg on the switch with "remote command switch sh ver" and if there a wrong conf-reg you must configured it in the rommon.

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Overall Rating: 4 (2 ratings)
Mark Yeates Wed, 08/13/2008 - 23:29
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Try changing the boot string to this.

boot system flash bootdisk:iosname.bin


satish_zanjurne Sun, 08/17/2008 - 21:22
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But when i use "show bootdisk:" command, it says invalid filesystem, or syntax error.

I mean to say if you look at filesystem, which i have pasted , i can't see any filesystem named bootdisk.

But i did try that also, but still it goes into ROMMON.

vaisharm Thu, 08/14/2008 - 02:09
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Hi Satish,

Please upload the following outputs in a text file (it doesn't mess up the formating):

- show ver

- show file systems

- show sup-bootflash: or show sup-bootdisk:

- show bootflash:

- show run | i boot

- show bootvar

Also, can you capture the boot sequence as well? That might provide a better understanding of the problem.

Capturing Text Output from Hyperterminal


Correct Answer
Johann Frey Thu, 08/14/2008 - 04:40
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look for the conf-reg on the switch with "remote command switch sh ver" and if there a wrong conf-reg you must configured it in the rommon.

satish_zanjurne Mon, 08/18/2008 - 04:26
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I used this command , and found that confreg = 0x2100.

I went to ROMMON and changed it to 0x2102.

Since then it is working fine.I upgraded the IOS, and switch is booting with new IOS withput problem.

But tell me, when i was booted and i used show version, so conf-reg it was showing me was 0x2102 , always.!!!

I need to understand how this command "remote command switch show version" is different than regular "show version". ??

I searched but did not find any convincing info, apart from it used to remotely execute the command.

Does anybody has got link for details on this command. ??

Also because of what this value changed to 0x2100 ??

vaisharm Mon, 08/18/2008 - 09:35
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In native mode the 'show version' output would show the config register value for the MSFC. However, 'remote command switch show version' would provide this output from the supervisor instead (the config register value that you see now would be for the SUP). 0x2100 means boot into ROMMON mode.

There are two ways to execute any command on the SUP in native mode.

1. You get into the SP mode using 'remote login switch' command and then execute show version or any other command on the SUP.

2. You use the 'remote command switch' to execute the command remotely on the SUP from the MSFC.

Search for 'remote command switch'.



burleyman Thu, 08/14/2008 - 05:26
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If you are in ROMMON post the output of dir bootflash: or you can do a show bootflash: if the switch in not in ROMMON.



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