Hello! I am experimenting with automatically partitioning, formatting and creating files on a new drive based on configuration. Systemd comes with all the building blocks nowadays to do this, but I am still struggling a bit.
I have created some partition definitions and ran systemd-repart to partition a drive according to those definitions. I am currently experimenting in QEMU, so I run this command: `system-repart --dry-run=no --empty=require /dev/vda` to partition the new drive. That works nicely. Now how do I format those partitions? Systemd-mkfs springs to mind -- so I will need to identify those partitions in /etc/fstab. My system is immutable, so I have to create /etc/fstab at the same time I create the various partition definition files in /usr/lib/repart.d. What is the best way to do so? These are the options I see: * Partition numbers (the X in /dev/vdaX) * PARTUUID and * PARTLABEL The partition number seems unreliable: Systemd-repart may leave out some low-priority partitions, which will shift down any partition defined later than the one left out. The partition UUID is calculated by systemd-repart based on machine-id, partition type and position in the GPT (relative to other partitions of the same type). But how can I calculate those UUIDs before running systemd-repart? There is also the problem that the partition UUID may also change when systemd-repart leaves out some partitions of the same type. Not perfect either. The partition label can be provided in the partition definition file, so this is the only piece of information I can have before running systemd-repart! But labels are prone to be short human-relevant strings -- and those tend to get reused in several places, etc. and udev ends up deduplicating the names. So those are more reliable than partition numbers, but not 100% reliable either. So far the only way I see is to set a random Label on my partitions so that I can put PARTLABEL=esp_a8322bf91e into /etc/fstab, combining the label with a UUID of my own making stored in the partititons .conf file. Would it maybe make sense to add a way to provide the partition UUID via the partitions .conf file as well? That way I would not need to add a UUID-part to my labels. Best Regards, Tobias _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
