Hugo Mills posted on Sat, 27 Jul 2013 20:44:48 +0100 as excerpted: > On Sat, Jul 27, 2013 at 08:52:50PM +0200, Hendrik Friedel wrote: >> As stated in the wiki, multiple-device filesystems (e.g. raid 1) will >> only mount after a btfs device scan, or if all devices are passed with >> the mount options. >> >> I remember, that for Ubuntu 12.04 I changed the initrd. But after a >> re-install, I have to do this again, and I don't remember how I did it. > > With Ubuntu, just install the btrfs-tools package. It should modify > the initrd correctly. > >> So, the other option would be passing the devices in the fstab. But >> here, I'd prefer UUIDs rather than device names, as they can change. > > This is why we don't recommend using device= mount flags. > >> Is this possible? What is the syntax? > > I don't believe it is possible. Finding filesystems by UUID is (I > think) a userspace-based thing, so you'd have to have an initrd anyway.
btrfs raid1 root here, was initr*less until I switched to btrfs which is broken with direct-kernel-root-mount rootflags=device=whatever syntax. UUIDs are indeed userspace -- udev/systemd. However, if your initr* includes udev, at least here, it "just works". I use root=LABEL=whatever here on the kernel commandline for root, and LABEL=whatever for non-root in fstab, but as long as udev has the directory in /dev/disk/*, mount should work with it, so root=UUID=whatever at the kernel commandline should work, as should UUID=whatever in fstab as the first field. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
