9800-40 HA Upgrade from 17.6.4 to 17.9.3

[scottsassin]

We are upgrading our 9800-40 HA Upgrade from 17.6.4 to 17.9.3. 

Can these versions be upgraded to directly from and to, or is there version steps?

Since this is an HA pair, can these be upgraded one at a time by failing over and upgrading the standby?

Can someone send me the procedure to upgrade them.

[marce1000]

            >...Can these versions be upgraded to directly from and to, or is there version steps?
           https://www.cisco.com/c/en/us/td/docs/wireless/controller/9800/17-9/release-notes/rn-17-9-9800.html#Cisco_Concept.dita_59a2987f-2633-4630-8c7b-a8e8aecdeaf7

             >Since this is an HA pair, can these be upgraded one at a time by failing over and upgrading the standby?
 - This process becomes automated once the upgrade procedure is initiated on the active controller , 

 M.

[M02@rt37]

Hello @scottsassin,

Since 17.6.x version you can go straight to 17.9.x.

As @marce1000 said, "This process becomes automated once the upgrade procedure is initiated on the active controller".

[Leo Laohoo]

Is the intention to upgrade the WLC but, most importantly, schedule the reboot of the WLC to happen some time in the future?

[Rasika Nayanajith · Accepted solution]

Yes, direct upgrade is supported. Please refer page 35 onward of below document for step by step instruction.
Upgrade using GUI is simple and it take care of all the complexities.
https://www.cisco.com/c/dam/en/us/td/docs/wireless/controller/9800/17-3/deployment-guide/c9800-ha-rau-apsp-apdp-issu-dg-rel-17-3.pdf 

HTH
Rasika
*** Pls rate all useful responses ***

[scottsassin]

How does the AP upgrade go? When are the APs reloaded after the upgrade. We have 300+ APs, and need to know how the AP upgrade process happens. All APs will be predownloaded with the new IOS. 

[Leo Laohoo]

Is "Enable Hitless Upgrade" enabled?

[scottsassin]

This will be an ISSU upgrade. We don't have another controller for N+1. 

I found the answer. The documentation says "Using the mechanisms of rolling AP upgrade and client steering with 11v, customers can upgrade their networks without scheduling a downtime window"

We will still schedule a downtime window. 

[Leo Laohoo]

Good luck.

[Rich R]

> Since this is an HA pair, can these be upgraded one at a time by failing over and upgrading the standby?

I think what you're hinting at is ISSU - intended to minimise downtime.  I've seen it demo'd in CiscoWebinars and it looks great - seems to work fine.  But in practice the install scripts are really finicky and buggy and it doesn't take much for it to go wrong.  So if you do want to try ISSU follow all the guidelines and instructions extremely carefully and let us know how it goes.

Personally we don't bother with ISSU because it's so temperamental.  We just do a standard install and reload - a few minutes downtime while they reload.  We have N+1 as well so the APs can go to the other WLC pair during that time if necessary.  I've seen ISSU leave the WLC in a messed up boot/install state that is quite tricky to recover from and usually requires 1 or more reloads to fix (so defeats the whole purpose of ISSU).  I think @Leo Laohoo has similar opinions on ISSU but others here may have got it to work for them.

https://www.cisco.com/c/en/us/td/docs/wireless/controller/9800/17-6/config-guide/b_wl_17_6_cg/m_upgrade_9800cl.html
https://www.cisco.com/c/en/us/td/docs/wireless/controller/9800/17-6/config-guide/b_wl_17_6_cg/m_issu.html

[Leo Laohoo]

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@Rich R wrote:
I think what you're hinting at is ISSU - intended to minimise downtime.  I've seen it demo'd in CiscoWebinars and it looks great - seems to work fine.  But in practice the install scripts are really finicky and buggy and it doesn't take much for it to go wrong. 

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LOL.  ISSU.  ROTF. 

@scottsassin, 

If ISSU is the intention, make sure TAC NAM/LATAM or TAC Europe is on the phone, more importantly, watching and ready to intervene.  When ISSU invariably fails it is a heart-pounding, b*tt-clenching, spectacular event of epic proportions.