gericb

Jumbo Frame Issues

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Hello folks!

 

I really lucked out on my very first install of DSM, 99% of everything worked, including the use of Jumbo Frames 9000.

 

What's been perplexing to me though, I have 3 other systems, all with 10/100/1000 built-in motherboard ethernet interfaces, either Realtek or Broadcomm, and though they are working

great at gigabit (1000Mbps), as soon as I enable Jumbo Frames at 9000, the control panel/networking comes back fine, seemingly indicating no issues -- BUT, when you re-start the system,

it no longer appears on the network, inaccessible completely. :shock:

 

So how can I tell which adapters/interfaces are supported and can handle it, without having to deal with this trial and error, erase & reload type of scenario?

 

Any thoughts or feedback most appreciated!

 

Cheers!

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Warning - opinion coming........if you are using this at home, Jumbo Frames really doesn't seem to do a lot of good and in my experience causes more problems than it solves.

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The Jumbo Frame works only if you have your switch configured to handle jumbo frames on ports where the stuffs it's' connected, if your switch do not support jumbo frame, you get all the packets fragmented because the switch ports have MTU fixed as standard ( 1500 or 1492 bytes ) so if you send a big packet the switch cut a big packet in several small like max MTU handled, check you switch and do the right config on every port on which you want enable jumbo frame.

At the same way, you have to configure every network card to manage jumbo frame.

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Much worse, all of your clients must support jumbo frames as well or the switch will have to cut the packets into smaller slices and you lose most of the performance gains you thought you might be getting via jumbo frames. Unless you have a really nice switch or your clients ALL support jumbo frames as well, you will most likely see less performance rather than more.

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Aigor: Unfortunately, what you were talking about, isn't the problem at all.

 

The router/switch is for sure Jumbo Packet ready and functional, as it's been in use for some time, same port, same cable.

 

I guess wasn't conveying my question clearly enough... I have 4 systems, all with Gigabit Ethernet Ports built into the motherboard, they ALL connect and function great at Gigabit speeds, HOWEVER, only ONE can successfully have Jumbo Packets enabled and work perfectly, the other THREE, once enabled and system restarted, seems to no longer function, can not be seen on the network.

 

So I am trying to figure out which adapters actually support/should function with that setting enabled, maybe some basic guidelines of chipsets/versions of network hardware, even if I go buy an add-on card, hopefully not only limited to Intel. The WORKING Dell Desktop has a Realtek RTL81XX PCI-E chip.

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