Updating IOS XE and ROMMON on Catalyst 4503E in VSS mode.

[Alexander Istomin]

Hello, experts.

We plan to upgrade ROMMON and IOS XE on Catalyst 4503E that is working in VSS mode.

ROMMON: from 15.1(1r)SG5 to 15.1(1r)SG18

IOS XE: from 3.8.4.E to 3.11.2E

I've read this guides:

1. ROMMON: https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/release/note/OL_30306-01.html

2. ISSU #1: https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/XE3-8-0E/15-24E/configuration/guide/xe-380-configuration/vss.html#pgfId-1320146

3. ISSU #2: https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/15-1-2/XE_340/configuration/guide/config/issu.html

But it still not clear for me, how to upgrade ROMMON on VSS cluster. There is no something like "ISSU for ROMMON", so as I understand it, this needs to be done separately on each switch. But what happens with VSS at this time? What could go wrong?

Please, guide me and share your experience how to do that in the best way. And without "IT LOOKS LIKE ALL NET IS DOWN! AAA-A-A!" :)

[Reza Sharifi]

Hi,

There is no ISSU for ROMMON upgrade. I recommend doing this in 2 phases if you can't have a long enough window to do both upgrades. So, 1 maintenance window for just upgrading the Rommon and a second one for upgrading the IOS. Also, with ISSU, the upgrade takes longer than doing it the traditional way. If you have a maintenance window, the simplest solution is to do it the traditional way. I think, if you go the traditional way, you can do them all in a one hour window.

HTH

[Leo Laohoo · Accepted solution]

Here's how I've done our Sup7E upgrade (with VSS): 

1. Copy the ROMMON file to the active supervisor card; 
2. Copy the ROMMON file to the secondary supervisor card; 
3. Verify the MD5 of the ROMMON file in the active supervisor card (verify /md bootflash:firmwareupgrade-151_1r_SG18.SPA 18a1899edc2eb4350e2563cab592e8db)
4.  Verify the MD5 of the ROMMON file in the secondary supervisor card (verify /md slavebootflash:firmwareupgrade-151_1r_SG18.SPA 18a1899edc2eb4350e2563cab592e8db)
5. Unpack the IOS-XE file into the active supervisor card (archive tar /x tftp://<TFTP_IP_ADDRESS>/<IOS_FILENAME>.tar bootflash:); 
6. Unpack the IOS-XE file into the secondary supervisor card (archive tar /x tftp://<TFTP_IP_ADDRESS>/<IOS_FILENAME>.tar slavebootflash:); 
7. Verify the IOS-XE file in the active supervisor card; 
8. Verify the IOS-XE file in the secondary supervisor card; 
9. Make sure the config-registry value is "0x2102"
10. Configure the boot variable string to boot the ROMMON and then the IOS-XE next.

conf t
 no boot system flash bootflash:<OLD IOS>
 boot system flash bootflash:firmwareupgrade-151_1r_SG18.SPA
 boot system flash bootflash:<NEW IOS-XE FILE>
 boot system flash bootflash:<OLD IOS>
end
wr

11. Reboot both units using the "reload" command. 

To verify, use the command "sh version | i ROM"

Once the pair has recovered and loaded with the correct version, remove the boot variable string pointing to the ROMMON: 

conf t
 no boot system flash bootflash:firmwareupgrade-151_1r_SG18.SPA
end
wr

And that should be it.  

WARNING:  ROMMON upgrade can take around 30 minutes.

[Alexander Istomin]

Leo,

I did upgrade (ROMMON + IOS) exactly as you wrote and everything went fine.

All update (ROMMON + IOS) lasted about 10 minutes.

The minor thing what i want to add to your plan is don't forget to check bootvar with:

show bootvar 

before doing:

redundancy reload shelf 

Thanks for the help!

[Leo Laohoo]

---

@Alexander Istomin wrote:

The minor thing what i want to add to your plan is don't forget to check bootvar

---

I deliberately did not include the option to check the boot-variable string because, to a novice, the output is long and confusing.