From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [linux-lvm] error mounting snapshot of ext3 filesystem In-Reply-To: Your message of "22 Jan 2002 13:59:26 CST." <1011729567.6638.40.camel@benway.cv.telegroup.com> References: <1011729567.6638.40.camel@benway.cv.telegroup.com> MIME-Version: 1.0 From: Pierrick PONS Message-Id: Sender: linux-lvm-admin@sistina.com Errors-To: linux-lvm-admin@sistina.com Reply-To: linux-lvm@sistina.com List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: Date: Wed Jan 23 08:46:01 2002 List-Id: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-lvm@sistina.com > Ok, I know that several discussions regarding snapshots have occurred in > the last month or two and I've tried to read every post from those > threads. Nothing I read has helped me solve my problem. > > Essentially, I can create a snapshot LV but I cannot mount it. > > I have compiled 2.4.17 with the lvm101-rc4 patch created from the source > archive. (I specified -with-kernel_dir appropriately.) I tried to > apply to apply the VFS-lock patch but the kernel would not compile after > having done so. (I wasn't sure if I needed this patch or not, but I > tried applying it anyway.) It fails like so: > > > make[2]: Entering directory `/home/spin/src/linux/fs' > gcc -D__KERNEL__ -I/home/spin/src/linux/include -Wall > -Wstrict-prototypes -Wno-trigraphs -O2 -fomit-frame-pointer > -fno-strict-aliasing -fno-common -pipe -mpreferred-stack-boundary=2 > -march=i686 -c -o super.o super.c > super.c: In function `unlockfs': > super.c:403: `mount_sem' undeclared (first use in this function) > super.c:403: (Each undeclared identifier is reported only once > super.c:403: for each function it appears in.) > make[2]: *** [super.o] Error 1 > > > Anyway, continuing without VFS lock: > I have three disks, an IDE disk /dev/hda, and two small SCSI disk, > /dev/sda and /dev/sdb and one VG with /dev/hda4, and the entirety of > both SCSI disks in it which is called main. > > /boot /dev/hda3 > / /dev/main/root (entirely on hda4) > /var /dev/main/var (entirely on hda4) > /tmp /dev/main/scratch (on both sda and sdb) > /home /dev/main/home (spread out across all three PVs) > > There are some PVs left on sdb, otherwise it's all used. > All of the filesystems are ext3, except /boot which is ext2. > > This is basically the sequence of events: > > [root@benway /]# lvcreate -s -n snaptest -L 200m /dev/main/root > lvcreate -- WARNING: the snapshot will be automatically disabled once it > gets full > lvcreate -- INFO: using default snapshot chunk size of 64.00 KB for > "/dev/main/snaptest" > lvcreate -- doing automatic backup of "main" > lvcreate -- logical volume "/dev/main/snaptest" successfully created > > [root@benway /]# mount /dev/main/snaptest /mnt > mount: block device /dev/main/snaptest is write-protected, mounting > read-only > mount: wrong fs type, bad option, bad superblock on /dev/main/snaptest, > or too many mounted file systems > > Trying to mount it as ext2 doesn't change anything. No matter which LV > I create the snapshot of, I cannot mount it and it fails with the same > error. > > Even if I create a small LV with ext3 filesystem entirely on sdb, and > then create a snapshot of it, it still won't mount. I can get this > small-all-on-one LV/FS scenario to work if I create an ext2 fs on the > LV. > > I know this is nearly exactly like the problems discussed in previous > threads but I haven't seen a solution yet that seems like it applied to > my situation. > > Thanks, > Aran > > > I do have the same problem : mount /dev/testlvm/snap /mnt/snap mount: block device /dev/testlvm/snap is write-protected, mounting read-only mount: wrong fs type, bad option, bad superblock on /dev/testlvm/snap, or too many mounted file systems I tried with -text2 or -text3 option and it's the same. What is the type wanted ? Is there a more documentated snapshot section where to found some more explanation ? Thanks in advance. Pierrick