EOS: L2 GRE Tunnel for several VLAN between 2 DataCenters

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we have the following szenario:
2 physically separated DataCenters.They are connected through L3 routing. in every datacenter we have one S4 VSB Chassis pair. They contain several vlans for servers. most of the servers are virtual (vmware) - but not all - the servers need both the same L2 vlan (same ip addresses) because of redundancy.

How can i setup one (or maybe several) L2 GRE Tunnels between this 2x VSB S4 chassis to connect the server vlans ? How can i get traffic of more than one vlan into the GRE tunnel ? tbp Interfaces ? Or do i need several tunnels ?

What are the current limits / experience / things to keep in mind with recent EOS (8.42)?

The EOS manual is very very poor regarding these szenario. I am looking for an config example and / or a best practise guide.
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Posted 2 years ago

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André Herkenrath, Employee

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This is exactly what VXLAN is made for. It is supported with S and K Series and the Release you are using. You need a tunnel license.
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vxlan is one option. But i think that L2 GRE Tunnel is much easier to configure (if someone knows how) and there is no special license needed.

Does anyone able to deal with a config example ?


Regards
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Straw, Glyn, Employee

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Hi Matthias, 

Does the following knowledge article help you ?

https://gtacknowledge.extremenetworks.com/articles/How_To/How-To-Configure-a-l2-GRE-tunnel-That-Brid...

Best Regards
Glyn
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Hi Glyn,
thats what i am look for.

To expect the limits, stability, performance, etc.  i think i have to do a lab setup.

Regards
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Straw, Glyn, Employee

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Hi Matthias, 

Here is an article i wrote for the GRE tunnel capacity limits by product line but they are also documented in the release notes or can be seen by typing "show limits" on the product to see the limit and the number in use.

https://gtacknowledge.extremenetworks.com/articles/Q_A/How-many-GRE-tunnels-can-be-created-on-an-S-S...

Hope this helps. 

Thanks 
Glyn
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Straw, Glyn, Employee

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the firmware may not enforce the limits but if exceeded the results could be unpredictable.