On Tue, 20 Aug 2019 11:19:04 -0600 Alex Williamson <alex.williamson@xxxxxxxxxx> wrote: > What about an alias based on the uuid? For example, we use 160-bit > sha1s daily with git (uuids are only 128-bit), but we generally don't > reference git commits with the full 20 character string. Generally 12 > characters is recommended to avoid ambiguity. Could mdev automatically > create an abbreviated sha1 alias for the device? If so, how many > characters should we use and what do we do on collision? The colliding > device could add enough alias characters to disambiguate (we likely > couldn't re-alias the existing device to disambiguate, but I'm not sure > it matters, userspace has sysfs to associate aliases). Ex. > > UUID=$(uuidgen) > ALIAS=$(echo $UUID | sha1sum | colrm 13) > > Since there seems to be some prefix overhead, as I ask about above in > how many characters we actually have to work with in IFNAMESZ, maybe we > start with 8 characters (matching your "index" namespace) and expand as > necessary for disambiguation. If we can eliminate overhead in > IFNAMESZ, let's start with 12. Thanks, > > Alex I really like that idea, and it seems the best option proposed yet, as we don't need to create a secondary identifier.
