• @danA
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    3 months ago

    and you shouldn’t be using any of those, since the order can and will change. The numbers are based on the order the devices and device drivers are initialized in, not based on physical location in the system. The modern approach (assuming you’re using udev) is to use the symlinks in /dev/disk/by-id/ or /dev/disk/by-uuid/ instead, since both are consistent across reboots (and by-id should be consistent across reinstalls, assuming the same partitioning scheme on the same physical drives)

    This is also why Ethernet devices now have names like enp0s3 - the numbers are based on physical location on the bus. The old eth0, eth1, etc. could swap positions between Linux upgrades (or even between reboots) since they were also just the order the drivers were initialized in.

    • @toynbee@lemmy.world
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      453 months ago

      I’m sure you know this, but to to supplement your comment for future readers, UUIDs are also a good solution for partitions.

      • lemmyvore
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        83 months ago

        I think OP’s point was that UUIDs can still change, but the stuff that makes up the /by-id/ names cannot. Granted, those aren’t applicable to partitions.

        • @toynbee@lemmy.world
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          3 months ago

          Right. I don’t think they and I are in disagreement - just trying to help expand their statement. Thanks!

        • @danA
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          33 months ago

          Right :) the original meme was just talking about drive names (/dev/sdX)

          • lemmyvore
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            23 months ago

            Depends on your definition of “unexpected”. OP was talking about reinstalls for example, where the root partition is deleted and recreated and its UUID will change as a result. If you copy an fstab from an older system backup you will fail the mount the root partition.

            UUIDs can also cause some reverse trouble if you clone them with dd in which case they won’t change but they should, and you end up with duplicate UUIDs.

    • @JasonDJ@lemmy.zip
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      3 months ago

      Back in my day, /dev/hda was the primary master, hdb was the primary slave, hdc was the secondary master and hdd was the secondary slave.

      Nothing ever changed between reboots. Primary/secondary depended on which port the ribbon cable connected to on the motherboard, and primary/secondary master/slave was configured by a jumper on the drive itself.

        • @pascal@lemm.ee
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          3 months ago

          If you had a Sound Blaster 16, you had an extra IDE port on the board, which DOS couldn’t see and you had to load special drivers to use them. Usually it was used for the CD-ROM.

    • 🐍🩶🐢
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      113 months ago

      I have a hatred for the enp id thing as it isn’t any better for me. It changes on me every time I add/remove a hard drive or enable/disable the WiFi card in the BIOS. For someone who is building up a server and making changes to it, this becomes a real pain. What happens if a drive dies? Do I have to change the network config yet again over this?

      • @Laser@feddit.de
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        3 months ago

        How is that happening? The number on the bus shouldn’t change from adding or removing drives. I could imagine this with disabling a card in UEFI / BIOS if that basically stops reporting the bus entry completely. But drives?

        Anyhow, if I’m not mistaken, you can assign a fixed name based on the reported MAC.

      • @hperrin@lemmy.world
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        3 months ago

        Use a systems rule to give it a consistent name based on its MAC address, driver, etc. I just had this exact same problem setting up my servers.

        root@prox1:~# cat /etc/systemd/network/10-persistent-10g.link 
        [Match]
        Driver=atlantic
        
        [Link]
        Name=nic10g
        
        root@prox1:~# cat /etc/systemd/network/10-persistent-1g.link 
        [Match]
        Driver=igb
        
        [Link]
        Name=nic1g
        
        
    • @mumblerfish@lemmy.world
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      33 months ago

      Having used gentoo for quite some time, there have been several occations where my network broke because the changing names and naming conventions of the network interfaces.