07-09-2025 09:22 AM
Hello,
Can we configure SSO/NSF betweent two 9500 paired using StackWise virtual and each having a single RP?
07-09-2025 09:44 AM - edited 07-09-2025 10:14 AM
hello man. Yes u can configure SSO/NSF between two Catalyst 9500 switches in a StackWise Virtual (SWV) pair, even with a single RP per chassis. but u need to know some stuff first: SSO works for L2 protocols (STP, LACP) and some L3 features (e.g., OSPF NSF, BGP Graceful Restart). Also there are some requirements like : Identical IOS-XE versions on both switches, proper setup active/stanby roles,,,. and fo so NSFaware routing protocols. and u have some limitations like: Full L3 stateful failover requires dual RPs. With single RPs, expect brief control-plane downtime during switchover and more.
However, I have had clients who preferred using only one RP link, and they experienced no issues whatsoever.... (thats real world man)
also man just so u know, I have extensive experience with the 9500, 9606R, and many other high performance devices. Feel free to reach out if u need in depth assistance with configuration.
hope it helps G
-Enes
07-09-2025 09:47 AM
also check these links G:
and this reddit link: https://www.reddit.com/r/networking/comments/1177ehv/cisco_9500_stackwise_and_bgp/
07-09-2025 10:08 AM
I will reply later for this issue I know why you are confuse here
MHM
07-09-2025 12:28 PM
@Piyush Dixit1 wrote:
Hello,
Can we configure SSO/NSF betweent two 9500 paired using StackWise virtual and each having a single RP?
Between them, no, because the pair operations as one logical device. I.e. you just configure SSO/NSF on the virtual switch.
Single RP, each device, should be fine.
Basically, a StackWise pair logically operates much as a single chassis with redundant sups. One's active, and one's standby. With SSO standby is hot for L2, and with NSF, standby is hot for L3.
One problem with StackWise devices only having a single RP, if you lose the RP, you lose all that chassis's connections. But, if you've have redundant connections to both pair members, you shouldn't lose any connectivity, but you will lose performance capacity.
If the standby StackWise member fails, migration to moving to active member probably under 50ms, i.e. like losing alternate line cards on the same chassis.
If the active StackWise member fails, compared to a single chassis with dual sups, transition time to standby becoming active, a bit more impactful, as again, all the prior active chassis ports lost, and (likely) just a bit slower to detect lost of active member. Overall, probably comparable to single chassis with dual RPs.
Also again, if either StackWise Virtual member single RP fails, you've lost half your forwarding capacity.
07-10-2025 02:51 AM
Hello @Piyush Dixit1
Please see here:https://www.cisco.com/c/en/us/products/collateral/switches/catalyst-9000/nb-06-cat-9k-stack-wp-cte-en.html#Highavailability
Chapter High availability
07-10-2025 02:59 AM
Start from
How many SVI I need to connect external router to both SW ? One' only the active will have UP SIV and it completely responsible of routing
External router see how many neighbor? Only One' active only will see from external router
Here come SSO/NSF it send FIB (which build from external router and active) from active RP to standby RP
What protocol use between dual RP ? It called RRP' which responsible of sync info from hot RP to cold RP in same chassis
MHM
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