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ASR920 Rommon - Boot loop


A question more so then anything else, I've searched through the forums and not yet found the answer.

About to upgrade a ASR920, checked the upgrade manual available which specified the following:

"If the ROMMON version is 15.6(24r)S and the Cisco IOS XE release is 16.6.x, the router fails in the auto
upgrade process during the migration to Cisco IOS XE release 17.x.x resulting in a continous boot loop"

The ASR in question is currently running 15.6(10r) coupled with IOS XE v 16.07, has there been any reported issues between these specific firmwares? 

EDIT: Follow-up question, was the issue reported from the manual completely bypassed with the automatic upgrades of rommon with newer version of IOS XE? for example, 17.3.1 only auto-updated rommon for primary while 17.4.1 automatically update both.

7 Replies 7

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I have already read this, it's a specific set of circumstance that does not apply to my scenarion: "If the ROMMON version is 15.6(24r)S and the Cisco IOS XE release is 16.6.x" - As clearly stated in my question, this is not the current ROMMON version running nor is it the same IOS XE release.

Lets ask this question - what was the current IOS /(XE) code running, what version you trying to upgrade ?

can you turn off the device, connect console, turn on device  and post complete boot logs (until it reload automatically figureout what is wrong ?)



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No OOB available, no direct physical contact to unit available. I am simply trying to avoid being looped out like the manual suggests. All the relevant data för version of software is in the original post.

Leo Laohoo
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Manually upgrade the ROMMON to the highest available version. 

With 17.X.X "ROMMON auto-upgrade", there is no guarantee that this feature will not break the router.  Cisco does not have the resources to test ROMMON firmware because this means the "testers" (if there is ever one left) would have to access a physical unit to test the ROMMON on.  And I know that there are no more "physical" unit(s) available for testing because everyone relies on IOS-over-Linux.  

Manual upgrades to ROMMON is risky buisness as you will be locked out remotely, which in turn will require physical access to the switch. It seems that at this rate I am to wing it and hope that the boot loader doesnt end itselfs during the regular upgrade attempt. Worst case I have to gain physical access with a "disk" with new rommon-firmware to do the upgrade on site manually.

@Slothmarine wrote:
Manual upgrades to ROMMON is risky buisness as you will be locked out remotely

I disagree.  I have been doing ROMMON upgrades since the 2800/3800 were first introduced and I have never bricked a router, switch or WLC.  

However, I have discovered a critical bug when I upgraded the ROMMON of a 9800-80. 

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