Change Lefthand MTU

Nikumba · 30 Jul 2013 at 10:37

We have a stack of HP P4500 Lefhands that I need to change the MTU on from 9000 back to 1500.

Now for the life of me I can not find the option in the GUI and nor can I find the answer in Google.

Anyone know how this is done?

Thanks

Kimbie

ASE001 · 30 Jul 2013 at 15:47

To change the MTU;

netsh interface ipv4 set subinterface "Local Area Connection" mtu=1500 store=persistent

To show current settings;

netsh interface ipv4 show subinterfaces

ASE001 · 30 Jul 2013 at 16:24

Are these Wintel servers, with an MTU of 9000 it looks like an iSCSI interface or something similar?

Is it SAN controller, perhaps it can't be changed, 9000 seems to be the standard setting for iSCSI.

:confused:

Nikumba · 30 Jul 2013 at 17:28

HP Lefthands are SANs so the setting needs to be set there, our newer ones have an MTU of 1500 so it would appear possible it can be set as both running SANiQ 10.5 with all the current updates

Kimbie

ASE001 · 30 Jul 2013 at 17:43

If it is an iSCSI interface then is should be set to 9000 (jumbo frames), so perhaps you should be changing the newer SANs to 9000.

If you decide to set all MTU to 1500 make sure you set the switches too!

Nikumba · 30 Jul 2013 at 18:10

Our SAN switches, and VM hosts are all set to 1500, so changing the lefthand is the easier option

Hellsmk2 · 30 Jul 2013 at 20:01

Nikumba said:
Our SAN switches, and VM hosts are all set to 1500, so changing the lefthand is the easier option

Configuring jumbo frames on your switches and hypervisors is still the better option.

Nikumba · 30 Jul 2013 at 20:28

Hellsmk2 said:
Configuring jumbo frames on your switches and hypervisors is still the better option.

Why? As everything we have looked at would suggest unless you are running 10Gbe you will not get a massive performance increase by using jumbo frames