L2 Overlay support for Nexus 5500

[pat.mchenry]

Hello,

looking for any solutions I can use to extend layer 2 networks over a layer 3 connection using Nexus 5500. I know QinQ and OTV, VXLAN are not supported, but could I use a GRE tunnel? Not sure that is supported on the Nexus either...having a hard time finding any documentation supporting the feature on the 5500 which leads me to think I don't have any options. The other end of the circuit would be a CSR - which from what I understand will support the needed protocols. We are also considering using a 3750 to accomplish this...maybe using L2TPv3 or anything else it might support.

FYI, this will be a temporary solution as we are ordering some 9Ks in a the future, but we need to get this working with what we have in the interim.

Any ideas?

Thank you, Pat

[Francesco Molino]

Hi

You have 1 csr on 1 end. Do you have another csr on the other end?
It will allow you to expand your vlans using vxlan.
I would go with that solution if you can have 1 csr more unless you what have it.

[pat.mchenry]

Francesco,

Unfortunately, no. We would need a solution that will work with the Nexus 5500 on one end.

Thx for the response.

[Sergiu.Daniluk]

Hi @pat.mchenry 

Unfortunately, Nexus 5500 does not have a lot of available features other then fabricpath, which doesn't apply to your situation.

The 3750 supports dot1q tunneling so that might be one solution:

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750x_3560x/software/release/12-2_55_se/configuration/guide/3750xscg/swtunnel.html

Stay safe,

Sergiu

[pat.mchenry]

Sergiu,

Actually, don't believe the 5500 platform supports fabric path - I think that was made available with the 5600s...

Does the 5548 support any GRE tunneling that could carry some L2 traffic over an L3 connection? And, Note it doesn't have to be over a L3 connection - We could also use the option of L2 tunneling as mentioned in the 3750X doc....would the Nexus support that?

I'll check out the 3750X solution tho for sure.

Thanks for the response - Pat

[Sergiu.Daniluk]

Hi @pat.mchenry 

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Actually, don't believe the 5500 platform supports fabric path - I think that was made available with the 5600s...

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Quite the opposite. All Nexus 5000/5500/6000/5600 and Nexus 7000 (all linecards, but depending on version) support fabricpath.

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Does the 5548 support any GRE tunneling that could carry some L2 traffic over an L3 connection? And, Note it doesn't have to be over a L3 connection - We could also use the option of L2 tunneling as mentioned in the 3750X doc....would the Nexus support that?

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Nexus 5500 does not support any overlay protocol, mainly because of the L3 capabilities, which are not built-in into the ASIC (carmel) - you need a L3 daughter card for it, compared with Nexus 5600 which supports quite a lot of features - this one has different ASIC (bigsur).

Also, keep in mind that at the time of manufacturing, Nexus 5500 was targeted as data center switch, with focus on low latency and unified ports. Soon after, VXLAN become popular, so Nexus 5600 appeared to overcome the lack of features support on Nexus 5000 series.

Stay safe,

Sergiu

[pat.mchenry]

Sergui,

"Nexus 5500 does not support any overlay protocol, mainly because of the L3 capabilities, which are not built-in into the ASIC (carmel) - you need a L3 daughter card for it, compared with Nexus 5600 which supports quite a lot of features - this one has different ASIC (bigsur)."

Are you saying that if our 5500 had the L3 daughter card, it could support overlay protocols or are you saying if it had the L3 daughter card it could support L3 protocols such as OSPF, EIGRP, OSPF but still would not support overlay protocols (including GRE tunnels)?

Thank you

[Sergiu.Daniluk · Accepted solution]

If your Nexus 5500 had the L3 daughter card, then you could run layer 3 protocols (unicast/mcast routing, FHRP, BFD). All of the supported Layer 3 protocols are listed here: https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus5500/sw/unicast/7_x/cisco_n5500_layer3_ucast_cfg_rel_6x.html  As you can see, there are no overlay protocols listed (including GRE).

Cheers,

Sergiu

[pat.mchenry]

Thx a bunch, Sergiu!!

Pat