In-Service Software Upgrade (ISSU) is not supported in Cisco SD-Access

[holger.moersfelder@global.ntt]

I want to share this limitation on ISSU for fabric enabled devices.

***Note*** ISSU is not supported via Cisco DNA Center or manually via the CLI in SDA.

See Release note - 2.3.5.x Section Limitations and Restrictions

In addition the limitation was mentioned before in this Bug Notes

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwa57024

https://bst.cisco.com/quickview/bug/CSCwe39441

This limitation will effect an ISSU capable fabric node like:

C9500/C9600/C9400 SVL - Border Nodes or Edge Nodes

C9400 Chassis with Dual-Sup - Edge Nodes

C9800 - WLC HA CLuster

Without ISSU any sda device have to be rebooted during software upgrade leading at minimum 3 minutes outage.

Any feedback or comments are welcome !

[jedolphi]

For WLC, ISSU **IS supported**, I have confirmed internally very recently.

For Border Node today, have 2x separate BNs (not SVL) with LISP Pub/Sub Control Plane. While BN1 is reloading, if the design is correct, B2 should take the traffic.

For Edge Node and BN in future, we are working on ISSU.

For Edge Node in the short term, you can dual-home endpoints to two different ENs **IF** the NICs are active/standby i.e. only one NIC is talking at a time. For L2 switch, you can dual-home to two ENs with FlexLink+, again, only one uplink can active at a time. To unpack this design further perhaps consider talking to your SE or CX representative.

Regards, Jerome

[holger.moersfelder@global.ntt]

Thanks for your reply !

Running SW 2.3.5.4 the ISSU feature is still disabled for WLC HA integrated in SDA fabric.

Which SW version have you checked for WLC HA ISSU support ?

[jedolphi]

Hi Holger, sorry for slow reply, it's fixed in 2.3.7.3 and 2.3.5.6. In mean time perhaps consider using CLI if that's appropriate for your requirements. Regards, Jerome

[Marc Aemmer]

Any known ETA for 2.3.5.6?

[alessandro.s]

Hi Jerome,

wondering why ISSU upgrades were disabled in 2.3.5.5 as i always upgraded CAT9600 and 9800 WLCs with ISSU in DNA Center without any issue. Also, when you talk about a fix in 2.3.5.6 and 2.3.7.3 do you mean ISSU will be available again for all the capable devices or for WLCs only? any plan to publicly release 2.3.5.6?

King Regards,

[holger.moersfelder@global.ntt]

Hi Alessandro,

the new releases should be available soon / mid April. Lets see what ISSU capability changes the new releases provides. The ISSU limitation is only for SDA enabled devices which was from the beginning.

Regards Holger

[alessandro.s]

Hi Holger,

many thanks for your reply. Despite the Release notes of DNAC 2.3.3.X states that ISSU is not supported, I can confirm ISSU for SDA enabled device was working in 2.3.3.7, as i upgraded, using ISSU, some Cat 9606 switches and 9800 WLCs so this is why i was surprised to see that the same was not possible in 2.3.5.5 but, yes, let's wait for 2.3.5.6 and see .

Regards,

[jedolphi]

ISSU is supported for 9800 WLC in SDA fabric. The 2.3.5.6 fix is supposed to make ISSU possible through the Catalyst Center UI. Prior to the fix being integrated into the UI, the 9800 ISSU can be executed on the CLI. 2.3.5.6 release dates should be available in next few weeks, but please understand things can shift due to a range of variables, so any estimate I give here is approximate.

ISSU is not supported for any switches in SDA at this moment in time. CLI ISSU may work on some switches in SDA fabric in some scenarios, but official support will not be announced until we have validated all SDA scenarios. There is some roadmap to make this happen and I'd encourage you to talk to your sales team about roadmap.

[alessandro.s]

Hi Jerome,

thanks for your clarification, so with 2.3.5.6 will be the support to use ISSU for 9800 WLCs via Catalyst Center UI but still not for switches in SDA. As i said, i was surpised about this 'cause when i was 2.3.3.7 (and, i canay, also in older releases) i upgraded 9600 switches and 9800 wlcs with ISSU from DNAC UI. So, about the switches, i'll check with the sales team to see if it's in roadmap.

King Regads,