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CRS-1/8 upgrade from 3.9.2 to 4.3.0

Hi everybody!

I'm trying to upgrade a CRS-1/8 from 3.9.2 to 4.3.0

1) It's a CRS-1 with redundant RPs, I think it's not a problem.

2) Current rommon version is 1.54. Also looks fine.

3) Procedure:

To minimize downtime I used a PCMCIA card with 4.3.0 previously installed in a LAB router.

Without powering down the router I removed both RPs.

I inserted my disk0: with 4.3.0 in RP0 and inserted RP0.

The router started to boot up, but it went into a boot up loop. It didn't show any errors or failures.

I broke the loop with Ctrl+c, and in rommon could't see disk0:.

To recover, I used this procedure, but didn't try the upgrade again.

Bootflash was corrupted. I assume I did it myself, but what should I do to prevent this from happening again?

Any advice?

Thanks, Diego.

Cisco Employee

CRS-1/8 upgrade from 3.9.2 to 4.3.0

Hi Diego,

to run 4.3.0 on CRS you need to upgrade rommonA and B with a version ≥ 2.01 beforehand.
Please note we officially support a PIE upgrade N+2. I.e. A direct upgrade from 3.9.2 to 4.3.0 is not supported officially.
It may work, though.
The alternatives you have is either Turboboot or an interim step e.g. 3.9.2 to 4.1.2, then 4.1.2 to 4.3.0.
But nevertheless you have to upgrade rommon first.


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