Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!swrinde!elroy.jpl.nasa.gov!decwrl!stanford.edu!neon.Stanford.EDU!kaufman From: kaufman@neon.Stanford.EDU (Marc T. Kaufman) Newsgroups: comp.periphs.scsi Subject: Re: WARM SWAP Message-ID: <1991Apr24.034539.10819@neon.Stanford.EDU> Date: 24 Apr 91 03:45:39 GMT References: <1991Apr24.003217.12018@wpi.WPI.EDU> Organization: Computer Science Department, Stanford University, Ca , USA Lines: 21 In article hamilton@kickapoo.cs.iastate.edu (Jon Hamilton) writes: > Weren't you ever taught that you don't do stuff to the >inside of a puter with it on?! Depends on the computer. All telephone stuff and some fault-tolerant systems (like Tandem) are designed to have stuff plugged and unplugged with the power on. It's not overly much work to design PC compatible stuff that won't be injured in a power-on plug-in =provided= you don't short the connector traces. It's too bad that most manufacturers would rather save $0.10 than do it, though. Things like SCSI busses, if implemented per the standard, are relatively immune from gross hardware catastrophe because the drivers are current limited. Again, its too bad that some folks who program the device firmware don't do sanity checking if the bus accidently wiggles. Maybe the SCSI-3 standard should specify a minimum performance standard with respect to bus errors. Marc Kaufman (kaufman@Neon.stanford.edu)