Need to Change MTU setting in my ps6500 equallogic box

The EqualLogic arrays support standard Ethernet frames and Jumbo Frames up to 9000 bytes (including the TCP header), and will detect path MTU, which is the ability to automatically detect the maximum frame size between TCP/IP end point.  Jumbo size is determined by the negotiation between the end points.

For replication, starting in Firmware v4.1, a new support-only command exists to persistently stop using jumbo frames for outbound replication traffic. You run this on the source group, and it applies to all outgoing replications.

GroupName> support repl-use-jumbos [yes|no]

-Joe

Hi Joe & don,

Thanks for your value reply.  Is there any option to modify 9000 bytes?

Thanks

sseereddy

I have a customer using HP Procurve 28xx series for iSCSI which are known for issues with flow-control as well as jumbo frames enabled at the same time... http://communities.vmware.com/thread/268078 . They now bougth a PS4100E they want to use for VMFS volumes.

When using flow-contol, I prefer not to use jumbo frames. Therefore, I woul like to set at EQL level. At ESXi 5.0 I keep the MTU at 1500 bytes..

Once iSCSI configured, I also only see one path, although RR is set on the datastore. In the vmkernel port binding I can see one still as last active. the other unused... Why not both as active which I am used to seeing?

Is it possible to hardcode MTU on the EQL for normal traffic just like replication traffic?

Kind regards.

to clarify: even if your san is set to mtu 9000 and the switchports are also set to mtu >=9000, IF THE ESXi is set to 1500, 1500 it is all along the way!

Best regards,

Joerg