Interconnect different vPC domains

[maria.sousa]

Hi,

i have a new challenge that is interconnect 2 different vPCs (nexus_9k#1,2 and nexus_5k#1,2), at this moment they are completely isolated, but now we need to interconnect them in order to pass traffic between  servers. After read a lot of best scenarios and best pratices i'm a bit confused about the best solution, because i need to avoid loop in case of same vlan ids but the mainly objective is performing L3 routing between vPCs domains.

I share some draws, but oppinions are welcommed.

Thanks in advance

[nazimkha]

The best option to connect two nexus vPC domains is by using double-sided-vPC as per your drawings.

However if you using routing, you will need to upgrade to the version which supports routing over vPC.

Routing over vPC supported from :

Nexus 5K : 7.3(0)N1(1)
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus5500/sw/release/notes/7x/Nexus5500_Release_Notes_7x.html#pgfId-622079

Nexus 9K : 7.0(3)I5(1)
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/7-x/release/notes/70351_nxos_rn.html

For vPC best practices and design you check the Cisco Live session :
https://ciscolive.cisco.com/on-demand-library/?#/session/14479207929320017eHp

If helpful, Please do rate the post and mark it resolved.

[dbeattie]

Hi,

I did this about a year ago on a migration from N7k to N5k6. The solution that I opted for and gave no issues was a full mesh of 4 vPC links for switching and a full mesh of 4 stand-alone links for routing. Routing links were configured as L3 point-to-point OSPF. I also used dedicated non-vPC links within each vPC pair for routing. I was able to establish OSPF peering through-out and then move hosts and HSRP from N7ks to N5k6s and then turn off the N7ks. Worked a dream. Just be careful about default route originate in OSPF.

Hope this helps,

Dave