Nexus 5548 With Fex 2248

[Jepoy Diaz]

All,

I currently have nexus 5Ks and 2ks interconnected and everything is working fine except L3 routing outside to another router. I can ping between SVI within the Nexus environment but I cannot ping a router that’s attach to the FEX port. Also do you have to create separate VRFs for each SVIs? Any help on this will greatly appreciated.

Thanks,

Jepoy                  

[Garry Cross]

You have not provided any configuration or detail info to provide an informed answer.

A router is just another host and if you have the vlans, and svi set up correctly you should be able to ping it.

If the router is being connected via an integrated switch there may be issues between the two switchports that are causing you trouble.

After that static or dynamic routing between the two is a different topic.

If you are using multiple vdc you need to be in the correct context.

If you are using multiple vrf's then you would have to qualify the ping command in order to ping it if it's not the native vrf.

[Reza Sharifi]

If you are using multiple vdc you need to be in the correct context.

I guess, you mean VRF, because the 5500 series doesn't support VDC.

HTH

[Jepoy Diaz]

Reza,

5ks only has 1 VDC and please correct me if I'm wrong on that statement. Also I don't think I have a L3 Daughter card installed as will, but how do you know if you have a Layer 3  Daughter Card?

Thanks,

[Leo Laohoo]

Do you have a Layer 3 daughter board installed on the 5548?

[Reza Sharifi]

Hi,

If you have multiple FEXs connecting to 2 5ks, you need to configure both 5ks for the port that is connected to the router.

Is the port connecting to the router in up and up mode.  Can you provide the config from the 5ks. Are FEXs connected using VPC?

HTH

[Jepoy Diaz]

Reza,

My setup is as Follows:

1: Two 5ks

2: 1 Fex

3: 2960-S Switch

The Fex is Connected to the  2 5ks with VPC  - Works just fine

The 2960-S is also connected to 2 5ks using VPC - Works just fine

Create few Vlans and SVI in the 5ks - Work Just fine

Base on my setup, I just want to add a router to the mix so I can route L3 traffic to  the MPLS cloud. Along with that I need to also add a Firewall to the mix so I can point my default route to that Firewall for internet  access.Do I have to have a L3 Daughter Card for this to work?

Should the router and the Firewall should be plug into the Fex or the 5 ks?

Thanks,

Jepoy

[Oleksandr Nesterov]

Hi Jepoy

1. If you want to perform any L3 operations (routing, hsrp etc...) on your n5k you will need L3 module and Base license which is free and lifetime.

You can check whether you have a L3 module by running "sh mod", and check the license by running "sh lic usage"

Please be aware that simple ping and even some routing may work without L3 card, but traffic will be soft switched and wil have huge latency and loss.

2. Connetion router and FW to FEX is not recommended.

There are few reasons

a. all local switched traffic is sent to N5K so if router will send some traffic to ports on the same fex - they will use Fabric link and it will become oversubscribed.

b. FEX does't support some multicast routing traffic which can change the expected behavior on the router ports.

c. if a router tried to send a bpdu's (like a switch) FEX will block it's link by default

To be sure that FEX works fine - connect a host to the FEX port and try to ping Nexus SVI or other host connected to the FEX.

If you have any questions please add config to the ports.

HTH,

Alex