External HD inquiry

My question pertains to the do's n dont's on using the external HD (ie, not unplugging the scsi cable while the machine is on, etc, etc.)

I'd like to ask, Is there a correct order in terms of turning on and off the MPC n external HD?
Should the external hard drive be turned on first before the MPC? and also when turning it off, which should go off first?

Thanks.

It depends on your setup. I got a external zip 250 SCSI and a external 1 gig hard drive SCSI. I have the OS on the hard drive so it can boot faster (I got the oldschool mpc2000, boots from a floppy disk). So I need to turn the hard drive on first then the mpc. When shutting off everything I shut the hard drive off last, cause usually I save to the hard drive last before I shut ANYTHING off.

General rule of thumb, first pozer on the external drives, then the mpc. There is no real order in which you should power down. You obviously don't power down a drive while you're accessing it (read/write).