In my previous blog on building a home virtualization lab, I mentioned about buying a budget Network Attached Storage (NAS) solution with iSCSI capability. I made a decision and bought the Thecus N7700PRO NAS. It has 7 Bays for hard drives, dual GbE NICs with 4GB RAM and dual Disk on Module (DOM) and for future growth and scalability, it has a PIC-e slot for 10GbE card. It does support one type of Intel 1 GbE card but for most deployments, you will not need 10GbE as dual GbE NICs on the unit would do just fine. In addition to that, it supports iSCSI, iSCSI thin-provisioning, multiple RAID volumes and Online RAID expansion and migration.
I've installed 4x 2TB HITACHI Deskstar 7K2000 in RAID 6 configuration. This configuration would give you a total of 3.722 TB of space. The reason I went with RAID 6 is because it can sustain 2 drive failures. Often times, one drive may fail but another one could also fail during the RAID rebuild process, as many of us have experienced with RAID 5 in test or production environments. This is especially true with larger capacity drives like the 2 TB that I am using. I am hosting 3 virtual machine for my vmware ESXi host and will be adding additional vmware host in next few days so I can dig deeper into vmware's High Availability (HA), Fault Tolerance (FT) and clustering capabilities.
I've thin-provisioned about 500GB for VMs. Here is the kicker though, you have to allocate space for iSCSI when you create the RAID volume. It will not allow you to do after the RAID has finished building. I ran into this issue during my initial configuration steps. When you build the RAID, pay special attention to the Data Percentage option and decide how much you want to allocate for data portion and how much of that should be available for iSCSI target/iSCSI thin-provisioning use otherwise you will have to break RAID and build it or buy more hard drives and make another RAID volume? Here is screenshot of that option:
I hope this helps anybody looking to build a home lab for virtualization or just needs to configure their N7700PRO NAS. Be sure to stop by at our Virtualization forum and post any questions or comments.