Question about jumbo frames

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jyi786

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I want to get new switches for my home network which are all running 10/100 ancient switches. All my equipment already support jumbo frames EXCEPT the switches, so they are the weakest link.

The question that I have is that in some of my NIC settings, there are settings that say 9013 bytes, and in others that say 9000 bytes. If I enable jumbo frames on a NIC that says 9013 bytes but the switch's specs say 9000 bytes, will it still work, or will it drop the packets?

Thanks!
 
it will work, but the packet will be fragmented causing a decrease in performance.
So, instead of sending out a single 9013 byte packet, it will get broken up into 2 packets.

at least, that's how I understand it.
But I could be wrong since I'm not a real networking guru :p
 
If the switch is set for 9000 and the workstation is 9013 it won't talk if it sends a full size packet. Switch will see it as an overrun. So set everything to 9000.
 
NetJunkie said:
If the switch is set for 9000 and the workstation is 9013 it won't talk if it sends a full size packet. Switch will see it as an overrun. So set everything to 9000.
Click to expand...

Sorry, I made a typo, I meant to write 9014 bytes.

So that means that I would have to get a switch that does 9014? I can't set my NIC to 9000 because it doesn't have that option; it only has the following:

1514 bytes
4088 bytes
9014 bytes

Edit: Will this work? http://www.newegg.com/Product/Product.aspx?Item=N82E16833130084
 
Last edited:
If you're just doing Gb..don't bother with jumbo frames. Very little (<5%) performance increase, and that's at 100% throughput.
 
I wouldn't worry about jumbo frames in a home network either.
I would leave all host devices set to 1514/1500

There are always advantages and disadvantages to utilizing any MTU size. But the best way I can express this is think of the size of the packet in terms of what happens when that packet gets corrupted/lost. The smaller the packet size the less that is lost, the larger the more. But this doesn't mean use the smallest packet size available either, as the smaller the packet size the more overhead you get from the increase in total number of packets.
At work, an ISP, on our broadband Ethernet services we only allow 1514 for non tagged and 1518 for tagged.

Another sticking point is hit when you look at your inet access. I doubt your ISP allows jumbo frames. So your INET router will probably have to fragment ever packet you send to the INET increasing the workload it is doing.

As other have said I would suggest 1514 on the host, and as long as the switches are set to something higher than that it will work.
 
Jumbo Frame option is not needed. Better to deploy a full Gig LAN than use Jumbo Frames; causes errors.
 
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