Now that it’s spring, it’s time for us to start building out our preliminary iSCSI SAN unit. Here’s the hardware shopping list:
$0600 Super Micro 4U/TOWER RM EATX BLACK ( CSE-942I-R760B )
- triple-module redundant PSU w/ 760W
- 4U case for either rack or tower use
- (9) 5.25” bays
$0020 20-pin front panel connector to breakout cable
- Converts the 20-pin connector to something that can be attached to normal ATX motherboards
- CBL-0067 30cm
- CBL-0085 15cm
$0050 Rackmount Rail Kit: CSE-PT26
$0320 (2) Spare PSU modules - PWS-0050(M)
- Spare PSU modules for the redundant PSU
- Useful to have a spare or two on-hand
$0600 (4) CSE-M35T1 (black) - SuperMicro SATA 5:3 backplanes
- These allow you to fit a total of (15) SATA drives into the (9) 5.25” bays
- There are other SATA 5:3 backplanes that you can use
- While we’re only going to install (3) of these backplanes, I recommend buying a 4th for spare parts
$0167 3848163 (1) INTEL PRO/1000 PT DUAL PORT EXPI9402PT gigabit PCIe x4
- Used for SAN traffic
- Eventually, we’ll upgrade to a quad-port PCIe or a 10GigE
$0167 1494573 (1) INTEL PRO/1000 PCI-X
- The PCI card is used to talk to the LAN and internet, no SAN traffic will flow over it
- You could use an inexpensive 10/100 PCI card, but with a dual-port NIC you can bond for high-availability
$0600 12-port Promise SATA-II PCIe x8 card EX12350
- CentOS5 automatically sees any drives attached to this card (when they are configured in JBOD mode)
- We’re going the SoftwareRAID route
$0305 TYAN S2927G2NR dual-Opteron Socket F Thunder n3600B (S2927) $0600 Opteron 2214 dual-core Socket F $0200 (2) 1GB memory modules $0100 (2) Socket F cooling fans (Cooljag CJC689C)
- (4) 1.8GHz cores should be plenty of horsepower to do use Software RAID instead of the Promise RAID software
- 2GB is probably minimal for RAM, 4GB would be better
$1800 (15) 500GB SATA-II drives
- 500GB is a good balance between price and capacity
Totals:
$3410 base system $1800 drives
…
The drive plan for this unit is:
(3) 500GB drives in 3-way RAID1 (mirrored) for the operating system, log files, and other support software
Either:
(10) RAID10 + (2) hot-spares (2) 5-disk RAID6 + (2) hot-spares
The pair of RAID6 arrays would give us about 20% more capacity (net of 6 disks vs 5 disks). So the RAID10 setup results in around 2.27TB while the RAID6 setup would give 2.72TB.
With an overall cost of around $5500 for the entire unit, the price per gigabytes end up as:
$2.36/GB for (1) RAID10 array $1.97/GB for (2) RAID6 arrays
Which is not terribly bad for a starter unit.