To really unlock the potential in VMWware Infrastructure you need some kind of network storage. The alternatives are few and are mostly very expensive. Fibre Channel has been the only alternative for quite some time, but it is so expensive that only very large organizations could afford it.  It demands both dedicated host adapters (HBA), switches and storage devices.

iSCSI is the new player on the block. By using IP to transfer blocks to the storage devices, a large amount of infrastructure can be reused to create a SAN – or you can just put your SAN on your existing network. This eliminates the cost problem while still delivering quite good performance. As with FC you can buy dedicated HBAs and switches, but they are expensive.

So, I have taken the low-cost road to iSCSI. As you can see on the on the lab page, my storage server is a home made 3U server with 15 500Gig disk drives. The operating system of choice is Linux which gives me a number of choices for the iSCSI software package. After testing a few of them, I chose ietd, or “The iSCSI Enterprise Target”. The reason for choosing ietd was that it supports VMware and are still being developed.

Some early benchmarks suggests that ietd in combination with Open-iSCSI gives me close to 108MB/s over a single 1Gbit/s link. Quite nice if you ask me :-)