Re: ext2fs resize?
Waye-Ian CHIEW <[EMAIL PROTECTED]> writes: > I'm presently trying to shuffle and resize several partitions on a > disk device without losing data. > > Can the ext2fs resize itself? > That is, can the filesystem shrink or grow in size to accommondate a > resized partition? Is there a tool to do this? None that I know of. > Can the ext2fs move itself? If the whole filesystem is moved up or > down (relative to the start of the partition), will it still work? Don't move the filesystem relative to the partition, move the partition instead. All operation of a filesystem are done relative to the partitions start so a relocation within the partition will not work. If you have some free space or an unused partition you can use either tar or cp (with the -a parameter) to copy your partitions around, make room for bigger ones, format them and restore the contents of the partition back. BE CAREFUL and if you can create a full backup use your chance. Torsten -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Re: ext2fs resize?
When Waye-Ian CHIEW wrote, I replied: A utility to pack the current content of a filesystem to one end (or the other, or the center) of its space would be possible for each filesystem type, but a general tool would be extremely difficult (probably impossible). For example, the original UNIX file system had all i-nodes at the beginning of the slice and allocated content blocks as near as possible to the i-nodes, the Berkely file-system, on the other hand, scatters sets of i-nodes accross the file-system space, and I suspect that the linux filesystems have other differences in detail - and we haven't even considered MSDOS, W$95 (which has at least two flavors), OS/2, etc. I have a spare ~400 Mb disk that I use in conjunction with cpio and gzip to handlew these situations. A spare HD is probably the best $100 you'll ever spend. > > Hello! > >> I'm presently trying to shuffle and resize several partitions on a disk > device >> without losing data. > >My answer to this is NOT authoritative, that is, I haven't looked >at the code. However, in general, partitioning doesn't move data >about; it merely updates a small file which delineates the sets >of diskblocks that comprise each partition. > >The filesystem lays >out the the blocks of its partition in accordance with it's policy >- the filesystem on /proc is very different to those on /usr, or >/, or /var which are in turn very different from that on /msdos. >The *nix data partitions (/, /usr, /var, etc.) are layed out with >a set of i-nodes at the beginning of the partition (or sets of >i-nodes scattered throughout) each of which point to the individual >blocks (or sets of blocks) which hold the file. The policy (or >format) for msdos is very different, and unknown to me, as are >the formats of /proc, etc. > > Yes -- and I'm looking for filesystem-specific tools that will shrink an > ext2fs > and a vfat partition. > > But wouldn't resizing be simple to do in principle? (Defragment the > filesystem and > move everything to the front of the partition, then change the total number of > blocks in the superblock?) > >> Can the ext2fs resize itself? >> That is, can the filesystem shrink or grow in size to accommondate a > resized >> partition? Is there a tool to do this? >> >> Can the ext2fs move itself? >> If the whole filesystem is moved up or down (relative to the start of the >> partition), will it still work? > >Thus partitions aren't easily moved or combined without foreknowledge of > the >format of the content. Thus, you need to backup each of the partitions >involved, re-partition, and restore the backups to the now empty, new, >partitions. HTH. > > Unfortunately, the problem over here is that backup isn't really feasible. > (It's also, theoretically, a very redundant operation.) > > And wouldn't _moving_ also be simple to do in principle? (Make all filesystem > references to disk blocks relative to the superblock, not the start of the > disk.) > > -- Ian!! > Pobody's nerfect! > > -- > To UNSUBSCRIBE, email to [EMAIL PROTECTED] > with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED] -- - Ralph Winslow [EMAIL PROTECTED] Mary bought a pair of skates upon the ice to frisk now wasn't that a crazy way her sweet young *? -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Re: ext2fs resize?
Hello! > I'm presently trying to shuffle and resize several partitions on a disk device > without losing data. My answer to this is NOT authoritative, that is, I haven't looked at the code. However, in general, partitioning doesn't move data about; it merely updates a small file which delineates the sets of diskblocks that comprise each partition. The filesystem lays out the the blocks of its partition in accordance with it's policy - the filesystem on /proc is very different to those on /usr, or /, or /var which are in turn very different from that on /msdos. The *nix data partitions (/, /usr, /var, etc.) are layed out with a set of i-nodes at the beginning of the partition (or sets of i-nodes scattered throughout) each of which point to the individual blocks (or sets of blocks) which hold the file. The policy (or format) for msdos is very different, and unknown to me, as are the formats of /proc, etc. Yes -- and I'm looking for filesystem-specific tools that will shrink an ext2fs and a vfat partition. But wouldn't resizing be simple to do in principle? (Defragment the filesystem and move everything to the front of the partition, then change the total number of blocks in the superblock?) > Can the ext2fs resize itself? > That is, can the filesystem shrink or grow in size to accommondate a resized > partition? Is there a tool to do this? > > Can the ext2fs move itself? > If the whole filesystem is moved up or down (relative to the start of the > partition), will it still work? Thus partitions aren't easily moved or combined without foreknowledge of the format of the content. Thus, you need to backup each of the partitions involved, re-partition, and restore the backups to the now empty, new, partitions. HTH. Unfortunately, the problem over here is that backup isn't really feasible. (It's also, theoretically, a very redundant operation.) And wouldn't _moving_ also be simple to do in principle? (Make all filesystem references to disk blocks relative to the superblock, not the start of the disk.) -- Ian!! Pobody's nerfect! -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Re: ext2fs resize?
Waye-Ian CHIEW wrote: > > Hello! > > I'm presently trying to shuffle and resize several partitions on a disk device > without losing data. My answer to this is NOT authoritative, that is, I haven't looked at the code. However, in general, partitioning doesn't move data about; it merely updates a small file which delineates the sets of diskblocks that comprise each partition. The filesystem lays out the the blocks of its partition in accordance with it's policy - the filesystem on /proc is very different to those on /usr, or /, or /var which are in turn very different from that on /msdos. The *nix data partitions (/, /usr, /var, etc.) are layed out with a set of i-nodes at the beginning of the partition (or sets of i-nodes scattered throughout) each of which point to the individual blocks (or sets of blocks) which hold the file. The policy (or format) for msdos is very different, and unknown to me, as are the formats of /proc, etc. Thus partitions aren't easily moved or combined without foreknowledge of the format of the content. Thus, you need to backup each of the partitions involved, re-partition, and restore the backups to the now empty, new, partitions. HTH. > > Can the ext2fs resize itself? > That is, can the filesystem shrink or grow in size to accommondate a resized > partition? Is there a tool to do this? > > Can the ext2fs move itself? > If the whole filesystem is moved up or down (relative to the start of the > partition), will it still work? > > -- Ian!! > > -- > To UNSUBSCRIBE, email to [EMAIL PROTECTED] > with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED] -- - Ralph Winslow [EMAIL PROTECTED] Mary bought a pair of skates upon the ice to frisk now wasn't that a crazy way her sweet young *? -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
ext2fs resize?
Hello! I'm presently trying to shuffle and resize several partitions on a disk device without losing data. Can the ext2fs resize itself? That is, can the filesystem shrink or grow in size to accommondate a resized partition? Is there a tool to do this? Can the ext2fs move itself? If the whole filesystem is moved up or down (relative to the start of the partition), will it still work? -- Ian!! -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
