I am running an old HP 6300 SFF for my server. I have the cache drive installed in the case and currently 6 4TB & 1 8TB(parity drive) HDD in 2 of these cages HDD Cage. These run on old salvged 240w Dell power supply. I understand that I must switch them on before I fire up the server and if I shutdown the server then I need to kill the power to these manually.

My question is, is this a good practice?

It is working for me but I do not want to leave myself open to issues cown the road. The cages have a connector for the power supply which is controlled by a switch. Then I use a 5 way SATA Power breakout for each one

Something like this http://www.add2psu.com/

would automate the process.

 

Make sure the power supplies have a good common ground connection, one good method is a wire with ring terminals on both ends connected to the mounting screws on both PSU's.