For those following my travails yesterday, there’s good news, and bad news (and the bad news may be really bad). This morning, it finally logged me in, but it takes half a forever from the time I type in the password and I actually get a desktop. That’s the good news. The bad news is that I can’t find my old data where I backed it up yesterday.
I had backed it up to a file system on sdb3. But when I went to look for it today after logging in, /dev/sdb3 no longer exists. All there is is /dev/sdb1. And when I try to mount it I get the message “type lvm2pv not recognized.” Just how screwed am I?
[Update]
I’m hosed. Sort of, depending on whether or not I can find a wizard. Fedora decided, without asking me, to format both my drives as a single file system. The data’s still there, but not easily found. To top it off, the second drive is dying (which I didn’t learn until this morning). So I’ve shut down the machine, and am going out to buy a new big drive, load a fresh OS on it (without the other drives present), and then see how to go about the recovery. Fortunately, the data is redundant on both drives, which may make it a little easier to find, even with the superblocks and tables munged.
[Update mid afternoon]
In doing the new install, I’m pretty confident that I fornicated with the canine. It probably asked me if I wanted to format both drives, and I didn’t look carefully enough at what it was asking me. But Fedora started the whole thing…
do a
ls /dev/mapper/
If it is a lvm partition, formatted with a filesystem it will show up there, rather than as /dev/sdXY. Typically you would then mount /dev/mapper/VolgroupWHATEVER-WHATEVER
if, instead, you created a filesystem on a /dev/sdXY partition that was marked as a lvm partition (which knoppix lets you do) you may be able to fix it by changing, via the fdisk utility, the partition type of that partition to linux, probably
As to your login speed tests two and three from my previous suggestions may apply.
And, regrettably, the default for a “clean install”, is usually to wipe the disk and install the minimal number of partitions.
And, to confuse matters further, if you did a reinstall and did not use lvm for your base install, and /dev/mapper doesn’t show anything, but fdisk shows a /dev/sda3 partition… you have to turn lvm on before mounting it.
the manual way is
modprobe dm-mod # install the device mapper
lvm vgchange -ay # have it scan the partitions and map the lvm ones
cd /dev/mapper #
ls
you can also see the size of your current partitions via fdisk. If it shows /dev/sdb1 as the size of your whole disk, you are well and truly screwed.
(and regrettably I have to run for the day. Best of luck with it)
fdisk shows a single partition. Type Linux LVM. So my data is really lost? How did that happen? Is it truly completely unrecoverable?
I didn’t create the partition yesterday. It was an old partition on another drive from an older version of Fedora. I just used it as a place to back up my data. I’m kind of in shock at the notion that I’ve lost everything, if it’s true.
Also, when I modprobe dm-mod, I get the message “Module dm_mod not found.”
AHA. You are in possibly in good shape, then, as this is your second drive, not your boot drive.
3 possibilities: (highest probability first)
1) sdb is no longer sdb, but sda or sdc or some other drive, recognised in a different order than before, with the new OS version. What does mount show as mounted? you can less /var/log/syslog or /var/log/boot or /var/log/messages to see what drives were recognised
2) lvm is not installed (try the lvm command), nor is the kernel module
yum install lvm # should hopefully install both lvm and the kernel module
3) Something else is wrong
I am really on my way out the door in 2 minutes (heading to the airport), my cell number is ************
I read your blog quite regularly and am willing to help out…
Gotta say that a blog forum is not the right way to debug this, trying to intuit all the possibilities is difficult. For example, the modprobe failing is possibly not a problem, that dm-mod functionality can be built into the kernel. If there is stuff in /dev/mapper then lvm is working.
I hope it is just your device getting recognised in a different order. You can also brute force look for other devices on your system via fdisk /dev/sda
fdisk /dev/sdc
fdisk /dev/sdd
etc.
lvm is installed, but I’m not familiar enough with the commands to know what to be looking for. Everything I do so far, though, indicates that the disk only has one partition. I’m afraid that the Fedora install munged it somehow (perhaps deciding to use it as RAID without tell me?).
I would like to continue exploring the /dev/sda, sdc/sdd etc theory? Then there are other options….
I just missed my ride, and now have about 40 minutes to spare because the taxi is faster 🙁
I would have emailed this info but I assume your email access is down.
No, I have email.
Well, Instant Messaging would be a bit faster than this blog back and forth, I am sitting in my IM accts now…
Dave is right, though; even if Fedora decided to mangle everything through lvm2, the physical disk devices (sda, sdb) should still *be* there. Possibly it changed naming schemes?
And, yeah, those of us who are paranoid old unix sysadmins like removable media (DVD burners, USB harddrives, remote systems) for backups for just this sort of occasion…