Jumbo frames in Nexus 5000

[skrowocsic]

Hello:

We have 2 Nexus 5000 Switch with n5000-uk9.5.0.3.N2.2.bin system image file.

The 2 Nexus are distributed in 2 centers and are connected directly.

In each of the switches there is an Oracle server. These Oracle servers are clustered and connected by a heartbeat link.

The Oracle administrator ask us to configure jumbo frames in the heartbeat.

How can I make this?

Thanks!!!

[rawlinsm]

Thank you for the quick response.

I will add it during our next maintenance window. 

[rickyhermawan]

Hi, that one works for me but it's enabling MTU 9126 on all interfaces. How to enable it only in specified interface?

And what's the disadvantage of enabling maximum MTU on all interfaces?
*ps : I'm using 10G link in all my network

[Amanda Hunt]

Hi,

You can't enable MTU per-interface on a Nexus 5000 or 5500, only per-switch.

[wes_ward]

As long as you are not doing routing on a 5K there is very little risk on turning it on.  If your 5K is Layer 2 only then only way it will get jumbo frames is if the server admins turn on jumbo support.  Typically jumbos are used on backend L2 connections between systems.

[Rob Roy]

Sorry this is a bit late into this discussion, but I have a pair of Nexus 5672's that are acting as my Data Center core. So, there is Layer 3 happening here. I have a Port-channel/VPC to a pair of ASA-5585's operating in a cluster, and I am being asked to enable jumbo frames to them on the Cluster links. Obviously I can't enable on per-port basis here, so, will enabling this globally be impactful? Thanks in advance

[lkumar2272]

Hi Rob, Did you enable jumbo on your switch? I am in a similar situation where I have to enable jumbo's on my 56128p pair which is the DC core. I am not sure if it has any negative impact. Would be great if you can share your experience. Thanks!

[amarhingmire]

Also, on 5ks if its only enable globally, how traffic will be handled on non jumbo frame supporting ports (like WAN links, inter DC links), will it get discarded ?