--- Les Mikesell <lesmikesell at gmail.com> wrote: > On Wed, 2005-04-27 at 10:44, Aleksandar Milivojevic > wrote: > > > You'd need to resize file systems after you import > partitions into MD. > > An e2fsck/resize2fs would take care of that. Do an > "fsck -f /dev/md0" > > (for example). It will complain that information in > superblock is wrong > > (partition size fsck sees is smaller than what it found > in superblock). > > Just answer "no" to abort question. After you did > fsck, you need to > > do "resize2fs /dev/md0". Repeat for all md devices you > created. > > > > For above, the file systems should be either unmounted, > or mounted read > > only. The best thing to do is to boot from CD into > rescue mode, and do > > all job from it. > > > > The reason is that MD uses couple of last blocks for > metadata > > information, and that space is no longer usable for > file system data. > > So your /dev/md* metadisks will be slightly smaller > than partitions you > > created them on. > > What happens if existing files are on these blocks before > you > convert? > > > When you are creating mirrors, make sure you list > devices in right > > order. Data is always copied from first disk you > specify to second > > disk. If you get them the wrong way around, you loose > data. > > Another approach that might be safer is to create a > 'broken' mirror > first by specifying the 2nd device as 'missing'. Then > you can build > a filesystem on the md device and mount it somewhere and > copy the > files over from the existing partition. Then unmount the > old partition, > remount the raid device in its place (adjusting > /etc/fstab to match) > and use mdadm to add the old partition into the new raid, > which will > hot-sync it to match the new setup. Good idea, I will give this a try this evening. Thanks for your input concerning this issue. > > There are some rather good HOWTOs on this question > (with much longer, > > detailed and better descriptions of migration process). > Use the Google > > Luke. > > I looked for this and found lots of info on building > RAIDs but none > about preserving an existing filesystem while converting > to a mirror. > Can you provide a link or a good search term to pick that > up? Also, > I have noticed that after syncing the mirrored drives, > you can split > them and mount a single drive from it into another > machine without > making an md device first. (For example, if one part is > on a > USB/firewire drive, you can plug it into a different > machine and mount > the /dev/sda? partition it becomes.) However, I don't > know if this is > harmful or not. Does anyone know if, after running a > while in this mode > it will still work correctly if detected as an md? device > (with or > without resyncing to a partner)? > > -- > Les Mikesell > les at futuresource.com > > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos > -- Lee Parmeter Emperor, linXos - The Flying Penguin http://www.linXos.com Linux Registered User #337161 'It's free. It works. Duh.'" - Eric Harrison The United States is NOT a democracy, it was founded as a Republic! God is not a republican or a democrat nor is His government a democracy! - Lee Parmeter __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com