SUP7L-E dual sup upgrade from release prior to 3.6

[kbailleux]

Hi,

I have to upgrade a dual SUP7L-E 4500 chassis from an old 3.4.3SG to 3.8E

I read in the release notes that an ISSU is not supported from releases prior to 3.6.0E.

Does it means there are really no ISSU upgrade paths between pre 3.6 and post 3.6 ? 

If not, what do you think should be the best way to upgrade with the less downtime ? 

Thanks for your advices !

Karim

[Reza Sharifi]

Hi Karim,

If the 2 sups are in redundant mode (SSO), you can simply load the new IOS into the primary and the backup sup, change the boot parameter, save your config and reboot the chassis in a maintenance window.  The entire reboot time is less than 15 minutes. The first 3 steps can all be done ahead of time and really during the window you are just rebooting the chassis.

Once booted, make sure the sups are in SSO mode (sh redun) and running the correct IOS.

HTH

[kbailleux]

Hi Reza,

Thanks for your suggestion, it was indeed my worst case scenario.

I though about making a 2 step upgrade to first upgrade to a supported release, but it seems it's really unsupported. And you know speaking about downtime to customers is always tricky ;-)

Rgds,

Karim

[Reza Sharifi]

Hi Karim,

I completely understand that customer downtime is always an issue. You can also follow this document to upgrade one sup at a time and this should not have any impact on production. There are several steps involved but maybe worth trying it. BTW, upgrade one sup at a time works fine on sup-8.

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/12-2/01xo/configuration/guide/config/RPR.html#wp1130637

HTH 

[russell.sage]

I have 4506-E with dual sups in SSO mode

Copied the new IOS-XE image 3.11.02E to active and standby supervisors Sup 7 or Sup 8. Verified the images

Redundancy reload peer command brings the standby supervisor up on the new image but in Standby Cold Standby

Therefore when you issue the redundancy force switchover there is an outage of approx 2 minutes.

All the documentation I have read indicates in SSO mode should be a millisecond failover

Can anyone tell me what should happen.

[Leo Laohoo]

First of, I would like to say "good" for taking the time to actually upgrade the firmware.
Next, and most importantly, read the Release Notes very carefully. Upgrading from 3.4.X to 3.8.X requires a ROMmon upgrade. Without a ROMmon upgrade the line card will reject the IOS file.
Finally, I will also agree with Reza's method of upgrading the firmware using the "old fashion way" because this is a method that has worked for everyone.

[kbailleux]

Hi Leo,

Thanks for you answer ! 

I read in the release notes a ROMmon upgrade was needed for SUP8 :

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/release/note/ol-38xe-4500e.html#pgfId-1329149

Are you sure it's also needed for SUP7L ? (it's currently 15.0(1r)SG10)

Thx !

[Leo Laohoo]

This chassis has dual supervisor, right?
"If dual supervisor engines are present, first upgrade your software to Cisco IOS XE 3.2.0SG or higher, then upgrade your ROMMON to version 15.0(1r)SG7 to avoid an uplinks issue (CSCtj54375)."
If doing a ROMmon upgrade, might as well upgrade to the latest version.

[kbailleux]

So if I'm already in 15.0(1r)SG10, I guess it's OK ?

[Leo Laohoo]

You are fine. 

I still recommend ROMmon upgrade to 15.0(1r)SG15 because, some time in the future, you'd rather this job is done than do in with time constraint hang over your head.