Netgate Discussion Forum
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Search
    • Register
    • Login

    Interfaces randomly swapped?

    Scheduled Pinned Locked Moved 1.2.3-PRERELEASE-TESTING snapshots - RETIRED
    5 Posts 4 Posters 2.7k Views
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • M
      mhab12
      last edited by

      After a power outage, a router froze as the power came back on.  It's not on a UPS, so I can assume the power was choppy during the first few moments.  I powered it down, then rebooted again.  It came right back up, only the LAN and WAN interfaces had been swapped.  Very odd - any theories on this?

      Running 1.2.3-RC1 built on Mon Apr 20 12:40:07 EDT 2009.  I know it's time to upgrade, but I was more concerned about getting the box back online at the moment.

      1 Reply Last reply Reply Quote 0
      • W
        wallabybob
        last edited by

        What are the interface names? (e.g. fxp0, em1, vr2 etc)

        Its hard to image how this might have happened.

        If your interfaces are PCI devices their names will depend upon the driver that claims ownership and the order in which FreeBSD finds them as it scans the PCI device tree and that won't change UNLESS you changed the slots between the time you configured the system and the time you started it up again.

        If your interfaces are USB devices I suspect the device names could be a bit more problematic - the device names MIGHT depend a bit on what other USB devices are present and what they are doing.

        1 Reply Last reply Reply Quote 0
        • M
          mhab12
          last edited by

          They're both PCI cards….em0 and em1.  The MACs are very close, but I can't imagine that having anything to do with it.  One is ::::*:e0 the other ends with :ee.

          1 Reply Last reply Reply Quote 0
          • B
            bkm
            last edited by

            If your bios has pnp enabled, it may have made changes similar to swapping slots without you actually doing anything. I suppose the bios could have been reset during the power outage if the motherboard battery died.

            1 Reply Last reply Reply Quote 0
            • jimpJ
              jimp Rebel Alliance Developer Netgate
              last edited by

              This kind of swapping is due to the probe order being changed somehow. IIRC, FreeBSD always probes the same way, but this can be influenced based on BIOS settings.

              Typically it's BIOS or hardware related, but it would likely happen regardless of the OS in your case.

              Remember: Upvote with the 👍 button for any user/post you find to be helpful, informative, or deserving of recognition!

              Need help fast? Netgate Global Support!

              Do not Chat/PM for help!

              1 Reply Last reply Reply Quote 0
              • First post
                Last post
              Copyright 2025 Rubicon Communications LLC (Netgate). All rights reserved.