On Saturday 13 November 2021 07:33:49 Andy Smith wrote: > Hello, > > On Fri, Nov 12, 2021 at 11:42:32AM -0500, Gene Heskett wrote: > > On Friday 12 November 2021 10:18:07 Dan Ritter wrote: > > > After you have set them up, mdadm.conf has things like this: > > > > > > ARRAY /dev/md/0 metadata=1.2 name=debian:0 > > > UUID=aeac6271:676b1852:04f077d6:fcd285d6 ARRAY /dev/md/1 > > > metadata=1.2 name=debian:1 > > > UUID=d74ff881:2e966c37:ec6ef1ec:75b8cdce ARRAY /dev/md/2 > > > metadata=1.2 name=debian:2 > > > UUID=7c56166b:0d5aed8b:a9d03c45:e9b8080c > > > > That doesn't appear to be true. I have run the create which seemed > > to be ok, then mkfs -text4 /dev/md0, then mounted it at /home2. > > > > But /etc/mdadm/mdadm.conf doesn't yet have any of that, only this: > > You don't need to list the arrays in /etc/mdadm/mdadm.conf since > udev assembles arrays based on the metadata that exists on each > device. It's fine for there to be no ARRAY lines in there. These > days it's only really useful in recovery situations or for setting > some special options per array. > > You can still do the > > # mdadm --detail --scan > > to find the lines to put in the mdadm.conf yourself. > > > And again, I don't trust UUID's as moving a drive cable to a > > different socket has invalidated the whole lot of them once before. > > I would much rather LABEL the array, and mount it in /etc/fstab by > > that label. > > There may be some conceptual error here. The UUIDs you would put in > /etc/fstab are FILESYSTEM UUIDs, not array UUIDs. Lots of things in > computing have UUIDs. > > After you put a filesystem on each array you can refer to the > FILESYSTEM label in /etc/fstab. These labels are internal to each > filesystem and nothing to do with any layer below, such as md. > > > LABEL as I recall is a journalctl function? Does it work on > > raid10's? Its been quite a while but fdisk didn't do labels, but I see it grew that along with GPT tables. But back in the day, ISTR adding a label to a drive was done by journalctl and I'd call adding a label to a drive a function. > Filesystem labels have nothing to do with journalctl. And I don't > know what you mean by them being "a function". > > Again, filesystems (can) have labels, these are a filesystem detail, > RAID doesn't know nor care.
So I see, but the names for md0 and md1 are shown as hostname:0 and hostname:1 > > Humm, now: > > gene@coyote:~/AppImages$ sudo mdadm --detail --scan > > [sudo] password for gene: > > ARRAY /dev/md0 metadata=1.2 name=coyote:0 > > UUID=8ad67ef1:a14d63ab:c684ec2b:42a0c011 > > > > So I should add that last line to which category in mdadm.conf? > > mdamd.conf doesn't have categories. You would just append that line > at the end, ensuring it is all on one line. Yup, that was kmails word wrap. I forgot to turn it off when I pasted that. > > > And for the time being use that UUID in /etc/fstab to mount it to > > /home2, right? > > No, because that is not a filesystem UUID. And you said you wanted > to mount the filesystem by label anyway. So put whatever label you > chose when you did mkfs (or when you did it form the installer). > > In a later email you did this: > > # mkfs -Text4 … > > and got an obscure error. > > That's because you did "-T" instead of "-t", which means something > completely different. You may want to get into the habit of doing: > > # mkfs.ext4 … > > instead as it's clearer and easier to remember. > > Cheers, > Andy Thanks Andy. Cheers, Gene Heskett. -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author, 1940) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene>
