Nothing has changed in udev, and udev is not the culprit or cause, it just makes the devices as the kernel expects.
The kernel assigns device enumerations (eth0, eth1, sda, sdb, even the old hda, hdb) based on the order the device is made known to the kernel. With disk drives, especially SATA and USB storage devices, the time that it takes the drive to be detected can vary between boots. Often you'll find that one SATA port on your board always beats another, sometimes you won't. This means your drives will appear to dance around between different sdX names with no consistency. Given that all drives now appear with these names, including removable ones, we could either fight against the instability (as we do for ethernet devices - your USB key would always be sde, a different USB key would be sdf, sdg, etc.) or we can embrace it. For drives, we opted the latter. This means that drive letters are expected to change, and thus you should not rely on them for more than one session. For all permanent references, use the UUID or LABEL of the filesystem on the drive. The relationship with grub is only a perceived one. In fact, grub has no matching or intelligence between sdX drives and its own designators. This is the reason it uses its own in the first place. Grub's device ordering depends entirely on the BIOS view of the drives, in particular this means grub does not see any drive not seen by the BIOS. Grub has its own issues as well; a favourite bug report is that grub changes *its* device ordering when adding or removing drives, for no readily apparent reason. (On my own machine, a new SATA drive on port 3 became hd0 shuffling up those on ports 0-2) The only mapping between sdX and hdN names is /boot/grub/device.map which is attempted to be kept in sync, but can fail between reboots. Switching grub to UUIDs solves both sets of problems. -- S-ATA Hard drives swapped https://bugs.launchpad.net/bugs/225175 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
