Dell MD3000i Active/Active

The MD3000i is an active/passive designed SAN.

One controller owns a virtual disk and the other controller is the standby (passive) controller for that virtual disk.

If you have multiple virtual disks (whether they are on 1 disk group or multiple disk groups), they go round robin on which their preferred controller is. You can manually change the virtual disk's preferred controller (as well as the current controller if the disk moved to the non-preferred controller for some reason).

I do assume you set up the iSCSI subnetting properly (2 subnets; one port per controller in each subnet) and not put all ports on the same subnet.

Some of the newer MD3k SANs have firmware updates that enable ALUA, which makes the paths look all active.

Amazing! Thanks!

Yup all setup correctly.

Can you tell me the MD3k (newer one) which make all paths look active, the are not actually active?

Thanks,

Martin

Typically ALUA makes both controllers allow IO to come into their front-end ports, and then internally it sends it on to the controller than owns the LUN/Virtual Disk/Volume and that controller actually writes it to disk (on the back-end).

This gives the impression of active/active, but is not really fully active/active as the LUN is still owned by 1 controller at a time.

I don't suppose, Oracle of SANs, that you know what revision of controllers that the firmware update supports? :)

Thanks for all your help with this :)

Hello Martin,

ALUA support is available on MD32xx/MD36xx, & MD34xx/MD38xx. ALUA is support on all versions of firmware for those systems.

Please let us know if you have any other questions.