CIMC upgrade from 3.0(3a) to 3.0(4r) or 4.0(2o)

[aniket0422]

Hello All,

We have UCSC-C220-M4S server running CIMC version 3.0(3a).

Can we directly upgrade from this version to 3.0(4r) version or 4.0(2o) version.

Is there any intermediate upgrade is needed.

I went through the release note but couldn't find any clear statement.

Can anyone help please.

[Steven Tardy]

https://www.cisco.com/c/en/us/td/docs/unified_computing/ucs/release/notes/b_UCS_C-Series_RN_4_0_4.html#id_83496

[Leo Laohoo]

3.0(3a) is already the "intermediate" version and direct upgrade to any version above 4.0 is fine.  

NOTE:  

1. Cisco's documentation of the process to upgrade the CIMC is incomplete and confusing.  It has been at this state since I first read it back in 2016 so I cannot be certain if it is deliberate, however, @Rasika Nayanajith has created an easy-to-understand guide to CIMC upgrade (Standalone and HA).
2. Whoever is going to do the upgrade, do not panic (aka "code brown"):  Also absent in any Cisco documentation is the time it takes to upgrade the C220 CIMC.   Be prepared for the chassis to be down for 75 to 80 minutes while the CIMC upgrade is in progress.  

[a12288]

It took me around 90 minutes to upgrade CIMC and there is no any Cisco documentation mentions the CIMC upgrade might take that long, worse yet, there is no indication or progress bar during the upgrade process for quite a while, ~30 minutes or even longer. If you did not know this, it is a really torture!

[Leo Laohoo]

Image the first time I found out about this -- It was a "butt clenching" moment no one will never forget.