Live 3TB Ethernet Frame Size - Jumbo Frames

Can the Ethernet frame size be changed from the default 1433/1500 or whatever the default is to 4K MTU ?

If so can it be done through the SSH ?

Erm… Got to put a note in here that the only way (without cracking open the case) to use the My Book Live is by the network port. If whatever tweak is made that disables the network interface then you’re left with a NAS that can’t be contacted and if one is not kitted out to take out te disc and connect it to a computer to fix the configuration then the My Book Live will have to be sent back to Western Digital so the repairers can laugh at it’s owner and charge a fortune to perform the simple fix.

Unless the idea is to change the configuration change manually once the My Book Live starts and not interfere with the NAS’s start–up processes. At least then once contact is lost, to regain control will be a simply button push or yank out the power cord and plug it back in.

The above answer did not ANSWER my original Question. I guess you dont know what the SSH is?

If you Add-Change the URL when your logged into the box, you change the end of the URL to /SSH

then you can login with the shell. Inside the “SHELL” can the ethernet frame size be changed ?

OH BTW this is done without ever “CRACKING” open the case.

Yes, I imagine you can do just about anything you want to within SSH if you know what you’re doing.

One question is, WHY would you need to enable Jumbo Frames?   

It about doubles the throughput to and from the device, I am backing up a 2TB Buffalo NAS, and I allready have Jumbo 4K blocks enabled on the Buffalo, which is an option built into the web interface. I am sure the ethernet chipset can do this, but where is the option to modify this setting ? I am guessing I would need to post my question on hacking my book site, at least they would understand the Linux kernal and its commands in the SSH shell.

Wow.   That hasn’t been my experience in enterprise networks…   Enabling Jumbos on my 10-GigE NFS / NAS cloud improved throughput by no more than 10%.

And given that EVERYTHING in the path (hubs, switches, routers, and endpoints) must also support jumboframes, it was determined that the effort was not worth it.

In fact, the only place where we’re still using Jumbos is on our legacy (Gig-E) backup network (the mesh between our fileservers and tape libraries) which is completely isolated.   All of our newer equipment, as well as the public-facing interfaces on our legacy equipment, are all back to the standard ethernet MTU.

By the way, you ought to be able to change the MTU on the MBL by issuing the command

ifconfig eth0 mtu 4000

or whatever you want…

MYBOOKLIVE:~# ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:90:a9:f6:05:f8
          inet addr:10.0.0.15 Bcast:10.0.0.255 Mask:255.255.255.0
          inet6 addr: fe80::290:a9ff:fef6:5f8/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
          RX packets:16293738 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2492940 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:548217637 (522.8 MiB) TX bytes:1161637061 (1.0 GiB)
          Interrupt:32

MYBOOKLIVE:~# ifconfig eth0 mtu 4000
MYBOOKLIVE:~# ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:90:a9:f6:05:f8
          inet addr:10.0.0.15 Bcast:10.0.0.255 Mask:255.255.255.0
          inet6 addr: fe80::290:a9ff:fef6:5f8/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST MTU:4000 Metric:1
          RX packets:16293831 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2492972 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:548237200 (522.8 MiB) TX bytes:1161642292 (1.0 GiB)
          Interrupt:32

I do know how to get SSH up and running and have done a few minor tweaks from within the bash Linux shell like altering the idle3 attribute on the drive and securing the FTP service a bit more than the default.

What I’m on about is that the only way to talk to the MyBook Live is through the network port and if a change is made to the networking components of the MyBook Live then you end up with a NAS that will not respond to anything coming from your network.  Altering the Ethernet frame size is altering ne Linux networking software component.  Now if there was to be a serial console available or the likes then if the network port goes dead because of a configutation change it would be pssible to establish another connection to the shell and correct tthe problem.

In this case if a configuration problem kills the networking capabilities of the MyBook Live then the configuration on the NAS’s hard disc has to be altered using another computer.

That’s all I was on about.  A warning to others should they wish to mess with any of the NAS’s network software comoonents and configuration.

Enabling Jumbo-frames via SSH is pretty much risk free.

SSH login uses very small packets usually, so there’s only a miniscule chance of Jumbos causing frames to get lost.   

The example I pasted above was done while I was VPN’d into my home network from my work network, and accessing the hub via a Linux workstation via SSH.  

So I had about 5 network sessions open when I made that change, and no ill effects were seen.

Worst comes to worst:  You hit the RESET button as explained in the manual and the network settings go back the way they were.  

In fact, if you use the method I describe above, that setting does NOT survive a regular reboot until you add that command to the startup scripts.