Thread: Jumbo Frames
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Old 16th March 2009
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schrodinger schrodinger is offline
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Quote:
Originally Posted by ai-danno View Post
First off, when an Irishman wishes you Happy St. Patrick's Day, that's just really really cool (to an Irish-American such as myself, anyway.) So Happy St. Patrick's Day to you, as well!

[...]
My pleasure, I hope you are enjoying the weekend. I know I am, although going to bed last night at 4am to get up for work this morning at 7 didn't help me start the week but two days off from the end of today will help a ton!

Quote:
Originally Posted by ai-danno View Post
[...]

On your jumbo frame issue, it seems as though you understand a salient point that bears mentioning for anyone else referencing this thread- all devices in your network that intend on taking advantage of jumbo frames of any size will need to all match the same size together. So in this example, if one device supports 7K sized frames, all devices in the network should appropriately be set to 7K as well, or frames they transmit to that particular host will eventually will become fragmented, hurting performance.
This is something that everyone is going to find out the hard way - or through a ton of reading! But definitely something that is a vital consideration when implementing the use of jumbo frames. I find the best thing to do is to start off at the manufacturers website for both your switch and network interfaces and get the data sheets for each. Find out the max jumbo frame size supported, if supported, and plan around the smallest-largest size that one device supports and try to match the rest everywhere else on the LAN.

Quote:
Originally Posted by ai-danno View Post
[...]
The only way around this 'lowest-common denominator' approach for flexible MTU based on host is through the use of VLAN's. Each VLAN can have it's own configured MTU, instead of relying on a single MTU used by all in the network. This extends the complexity of your underlying network setup, though, and necessitates a connecting switch capable of VLAN Trunks (not the ether-channel-style trunking (aka, bonding)) so that each switch port can transmit on multiple VLANs simultaneously.
I am actually using VLANs in my setup, here -> http://www.konundrum.org/lanbuild.pdf (Yes, it is a bit complicated for a home LAN :P ) The problem is I will be using jumbo frames across VLANs.

Quote:
Originally Posted by BSDfan666 View Post
OT: My great grandmother was from Ireland, she immigrated to Canada.. St. Patrick's day is celebrated on the 17th March here though.
That's because St. Patrick's day is the 17th of March :P That's funny, my grandfather was Canadian and moved to Ireland! He and his sister were separated very early in their lives. He lived most his life in Ireland and she in Canada.
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