The basic idea is instead of letting the backplane or computer power the drive, we do instead with our external power supply. According to the storage controller's firmware, phy down == hotplug removed, which can be achieved by removing power to the target. This is 100% authentic and equal to walking up to a system and pulling/reinserting the disk by hand.
Parts list:
- Acquire a PDU e.g. those things that let you power servers on/off remotely. You really just need the ability to twiddle the power source remotely via SNMP or a web interface.
- An external molex power supply like this.
- Backplane to breakout phy and power separately for any SAS/SATA disk
- A SAS/SATA cable which has the composite male edge like the drive does and breaks out the phys and power.
- http://www.cs-electronics.com/sas-cables.htm
- SAS-7P82-P/1m
It's pretty inexpensive, with a nice managed PDU and all the parts to automate 1 disk amounts to $80 per port. You can use the PDU for other neat things too like say inserting and removing an external
USB hub, and it's connected peripherals, by controlling it's power source.
The equivalent functionality as part of an actual SAS/SATA target emulator could cost you between 15-20K. The vendor whom I have the most experience with this product, who will remain nameless out of respect; required an exceptional amount of upkeep and would break for seemingly no reason at all. Instead of purchasing additional target emulators for fault injection, we instead installed disk pullers
everywhere for a fraction of the cost and with virtually no maintenance.
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