I have VMPlayer 12 running a CentOS 7 disk. Works fine. However I wish to change the disk from UUID booting (fstab) to the old style LABEL. (so I can export it and use on another machine). fdisk -l /dev/sda Disk /dev/sda: 21.5 GB, 21474836480 bytes, 41943040 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x0001c6d3 Device Boot Start End Blocks Id System /dev/sda1 * 2048 20482047 10240000 83 Linux /dev/sda2 20482048 22530047 1024000 82 Linux swap / Solaris /dev/sda3 22530048 41943039 9706496 83 Linux however when I run: e2label /dev/sda1 / e2label: Bad magic number in super-block while trying to open /dev/sda1 Couldn't find valid filesystem superblock. Three questions: 1) Am I doing something wrong? 2) Is there a better way? 3) How do I support VM formats (VBox, VHD and VMWare) easily? Thanks, Jerry
> However I wish to change the disk from UUID booting (fstab) to the old > style LABEL. > (so I can export it and use on another machine). > > however when I run: > e2label /dev/sda1 / > e2label: Bad magic number in super-block while trying to open /dev/sda1 > Couldn't find valid filesystem superblock. > > Three questions: > 1) Am I doing something wrong? > 2) Is there a better way? > 3) How do I support VM formats (VBox, VHD and VMWare) easily?Is this an xfs filesystem or an ext4 filesystem? I could be wrong, but I suspect that e2label would only work on an ext2/3/4 filesystem. The default filesystem in RHEL/CentOS 7 is xfs. It looks like you can check labels on xfs filesystems with xfs_admin -l </path/to/filesystem> and you can set a label on an xfs filesystem with xfs_admin -L "<your label>" </path/to/filesystem> If you run "blkid" on your system it will give you all labels for all disks connected to your machine for any filesystem types that it understands. I don't think this has anything to do with physical or virtual disks or virtual disk formats either. Here we are just talking abut filesystems. Hope this helps. Barry
Hi Barry, It is an XFS file system. I ran the command: xfs_admin -L "/" /dev/sda1 and it says /dev/sda1 contains a mounted file system. fatal error. Now what? Thanks Jerry
Jerry Geis wrote:> I have VMPlayer 12 running a CentOS 7 disk. Works fine. > > However I wish to change the disk from UUID booting (fstab) to the old > style LABEL. > (so I can export it and use on another machine).<snip>> however when I run: > e2label /dev/sda1 / > e2label: Bad magic number in super-block while trying to open /dev/sda1 > Couldn't find valid filesystem superblock.<snip> And the answer is that the mount handling is broken in 7, and I've filed a bug over a year ago. The workaround solution is to *not* put slashes in the LABEL; instead, do e2label /dev/sda1 root or, another filesystem, to use what we use, e2label /dev/sdb1 export1 which we mount as /export/1. Alternatively, mkfs.xfs -L /dev/sdb1 export1 mark