Hot Swap question

Discussion in 'Hardware' started by mgookin, Nov 29, 2010.

  1. I think we all agree everything usb, firewire, ethernet, etc. can all be hot plugged.

    But with respect to eSATA, com ports and other connectors, what can be hotswapped and what can't?

    internal SATA
    DVI rear port connectors
  2. The internal SATA cable: unplugging it while the system is up and running is asking for trouble. Especially the SATA cable to the system disk drive. Don't know about the external SATA.

    DVI - it is the video cable. Shouldn't be a problem. It's best to have the monitor powered off when you connect/disconnect the cable.
  3. I've had multi-monitor video set ups get fouled from plugging or unplugging a DVI connector when powered... enough trouble that I had to reinstall the video driver and reset all invidual settings. Now I make it a point to make sure the power is off before I plug/unplug a video card connection. Might not make any difference with a single monitor, however.
  4. There are "hot swappable drive bays". Can't you replace the system drive on one of those so long as the swapped-in drive was formatted on that same computer and has the same video setup? Perhaps do the same with the internal SATA connectors??

    I've unplugged/plugged-in a secondary SATA drive while running during troubleshooting. That's been OK so long as the drive isn't unplugged for too long.
  5. My server is set up with mirrors and shadows on SATA drives and I have read about hot swapping them while the system is up (that's what it's made for; always on) so if a disc fries you can keep going, but I just don't understand how disc management would react. Fortunately it's never come to that. Seems like as long as the clone is happy, you're good to go. You can also rotate in and out a third clone for ultimate on-site backups.

    Since DVI hot swapping has caused problems, I would guess that holds true for other video out connectors as well - hdmi, etc. I think I remember hot plugging the legacy VGA in the past but that's moot today.

    Thanks for the feedback. I'll wait for the weekend to reconfigure some monitors.
  6. jprad


    The concept behind a hot-pluggable drive bay is pretty simple, it's data and power connectors have different length fingers so that the data, system ground, and bus voltage are staged. Data is the first to be connected, then ground and finally bus when the drive tray is inserted and the opposite staging occurs when you remove the drive.

    But, that's only half the battle. You're drive controller has to be hot-pluggable aware and that's typically only found in high-end RAID controllers, not commodity onboard controllers.
  7. There are hot-swappable drive bays available as 3rd party add-ons. (When I've seen ads for them, I've not noticed any controller "requirements" or restrictions.) I suppose those bays would include some software to make the onboard controller, "aware"?
  8. jprad


    "It is common for a system to be described as capable of hot swapping when it really is only doing warm swaps. True hot swapping requires support from all of the components in the system: the RAID controller, the bus (usually SCSI), the enclosure (which must have open bays for the drives so they can be accessed from the front of the case), and the interface."
  9. Catoosa


    The hard drive hot swap removable drive bays I have purchased all came with a required software installation disk. I never used the hot swap feature as I felt it was safer to turn off the PC to swap the hard drives.
  10. Well I was talking about a typical desktop PC with SATA connection to the harddrive (typically only one) and DVD-RW (typically only one). Unplugging such internal SATA cable to the system disk while the system is up and running... I don't think it's cool.

    Of course if you have the hot swappable drive bays and the hot swappable disks which are designed for hot swaps... sure no problem.

    Be honest I wouldn't even open a computer chassis while the system is up and running. I always unplug the main power cord before doing so. Just a matter of taking precautions.
    #10     Nov 30, 2010