Sadly the performance of Open-E DSS V6 is totally disappointing as well as the stability.
Now the question is - is this due to ESX 4.1 or Open-E DSS V6 ?
Would you recommend to upgrade the DSS V6 16TB to DSS V7 16TB and buy the active-active iSCSI package? ( Well this is a question of the price in the end - if vSphere 5 or DSS V7 is cheaper and what would you suggest is the main reason for those trouble ? )
Or could it be the hardware from the Open-E Systems?
I've two identical system here based on a Supermicro X7 Mainboard.
Each system has two Xeon 5160 and 16GB Memory.
Per system there is a HP P400 with 512MB and BBU connected to 8x 300GB 15k SAS ( 2x 4 disk RAID5 arrays ) and a HP P800 with 512MB and BBUs connected to 5x 2 TB disks at RAID5 and 3x 1,5TB disk running at RAID5. Those 1,5TB disk will move out and will be replaced with 120GB SSDs as soon as they will arrive here.
Onboard NICs are used for WebGUI and Heartbeat.
Each system as 3x PCI-X Broadcom Dual GbE NICs. The PCI-X NICs are used for iSCSI with MIPO and two are used for Sync.
In the end I only get a total of about 600Mbit max Network traffic over all 4 iSCSI MIPO NICs
With a live CD I've already tested disk speed and network speed. disk speed was max at ~330MB/s max / ~130MB/s min and 270MB/s avg for the 4 disk SAS raid 5 arrays. And for the 5 disk RAID a max with ~ 320MB/s and a min of ~272MB/s.
Benchmarked iSCSI MIPO to a RAM iSCSI Disc was ~ 450MB/s ( using 4 NICs which is quite nice ).
So how comes that with Open-E DSS V6 the performance drops so much?
Copying VM's from an iSCSI Server which is easy able to handle ~ 3000 Mbit to the Open-E System I only get up to 600Mbit.
Copying from two "old" iSCSI Servers to each other I get about ~ 2500 Mbit.
There has to be a bottleneck either with Open-E or with VMWare and Open-E DSS V6 or with the hardware and Open-E?
Cause with Windows Storage Server 2003 x64 and a Win XP live CD all works as fast as it should.
It takes about 10min to create 3% of a 512GB virtual disk for a VM at the Open-E iSCSI Storage.