On 2018-02-01, Nicolas George <geo...@nsup.org> wrote: > > > David Wright (2018-02-01): >> As far as finding the swap partition with fstab, ISTR a workaround. >> Without the details, you make the swap partition with a tiny >> filesystem in it, which gives it a stable UUID and LABEL. You then >> specify an offset in every reference to its use, which skips over >> the filesystem at its start. > > What are you trying to achieve with this baroque contraption? > > If a swap is encrypted normally, then just use its UUID. > > If a swap is encrypted with an ephemeral key, that means its contents is > not wanted after a reboot, so there is no need to preserve the key, > obviously. As to how to specify it in fstab, you need to use the name > declared in crypttab.
Unfortunately my crypttab (which I've never touched or looked at) reveals the following: # <target name> <source device> <key file> <options> cryptswap1 /dev/sda5 /dev/urandom swap,cipher=aes-cbc-essiv:sha256 Which is dangerous because that dev/sda5 gets wiped out at every (re)boot. curty@einstein:~/tips$ find -L /dev/disk -samefile /dev/sda5 /dev/disk/by-partuuid/00065379-05 /dev/disk/by-path/pci-0000:00:11.0-ata-1-part5 /dev/disk/by-id/wwn-0x50014ee2b0b1534b-part5 /dev/disk/by-id/ata-WDC_WD15EARS-22MVWB0_WD-WCAZA8328525-part5 I probably should change my crypttab (as a sane precaution) to: swap /dev/disk/by-id//dev/disk/by-id/ata-WDC_WD15EARS-22MVWB0_WD-WCAZA8328525-part5 /dev/urandom swap,cipher=aes-cbc-essiv:sha256,size=256 Still, I'm uncertain what goes into /etc/fstab. /dev/mapper/swap none swap sw 0 0 ? > Using filesystem labels and UUID is IMHO a very bad design, because they > reside inside the filesystem itself. Better use LVM, partition names or > partition UUIDs. > > Regards, > -- “True terror is to wake up one morning and discover that your high school class is running the country.” – Kurt Vonnegut
