Re: Copying a FreeBSD install to a smaller disk
On Thu, Sep 11, 2008 at 05:19:55PM -0700, Chris Weiss wrote: > How would I go about copying an existing FreeBSD installation to a smaller > disk? > > I've got a 3rd FreeBSD install I can boot from and store temporary > files on, all the disks are in the same hardware, so there's no > reconfiguration other than the boot device name and interface (IE > -SATA ad4 will become IDE ad0). The disk is partitioned using the > "default" sysinstall values and the contents of the larger disk will > fit on the smaller disk, although I need to increase the size of the / > and /var slices on the target to hold everything (/usr is fairly > empty, so it'll easily fit on the smaller disk). > > For now, we'll say ad0 = new smaller disk, ad4 = boot BSD disk, and > ad6 = the BSD install I want to clone. > > The path I've been going down is to manually partition and slice ad0 > create ad4/mnt/source and ad4/mnt/target and mount /var, /tmp, etc > from ad0 and ad6 and manually copy the files. But I'm stuck on how to > handle /, since it'll have dev and proc and such. > > Any thoughts on how to do this, or on a completely different approach? > I'm not aware of any 3rd party tools that'll deal with shrinking > FreeBSD partitions. > > Thanks in advance for any help you folks can give! Seems like you are generally on the right track, though some of your mounting seems backwards to me. First, as you have indicated, manually slice, partition and newfs the new disk (ad0) to match what you want to have on it. If you are making an identical, just smaller, disk to ad4, then do a df and see what slices and partitions are being used on ad4. Probably it is one slice, divided into several partitions. While you are at it, look at each of the filesystem sizes and make sure you will have room on the new, smaller disk. You want at least the current used size + 10%. Really you want more to actually operate. Presuming you want a single bootable slice (ad0s1) which is then divided in to partitions for: a: / b: swap d: /tmp e: /usr f: /var g: /home Do: fdisk -BI ad0 Creates a single bootable slice with default MBR (good enough). bsdlabel -w -B da0s1 Writes an initial label and boot block on the slice bsdlabel -e da0s1 Puts you in edit (vi by default) with the current condition of the partition label showing. If it is new, it will only show a 'c' partition covering the whole available size of the slice. Edit this page by duplicating that 'c' line for each real partition you want to have and changing fstype from 'unused' to '4.2BSD' on the a, d, e, f, g partitions and 'swap' on the b partition. In the end you will have something that looks about like: # /dev/ad0s3: 8 partitions: # size offset fstype [fsize bsize bps/cpg] a: 5242880 4.2BSD2048 16384 32776 b: 2572288* swap c: 783168750 unused 0 0# "raw" part, don't edit d: 1048576* 4.2BSD2048 16384 8 e: 4194304* 4.2BSD2048 16384 28552 f: 6291456* 4.2BSD2048 16384 28552 g:** 4.2BSD2048 16384 28552 You need only specify the sizes. You can put '*' for the offset and the bsdlabel utility figures it out correctly. Also, you can put '*' for both size and offset on the last partition and it will use all the remaining available space. Don't do anything with the actual 'c' partition. Remember that sizes here are in 512 Byte blocks/sectors. The sizes I have here are for a disk I happen to have handy at the moment to look at. a: 256 MBMount as; / b: 1,256 MB swap d: 512 MB " "/tmp e: 2,048 MB " "/usr f: 3,072 MB " "/var g: 31,096 MB " "/home Then do a regular newfs on each real file system a, d, e, f, g newfs /dev/ad0s1a newfs /dev/ad0s1d etc for e, f, g Once you have the new disk created, I would do the rest all in single user mode. Boot to single useri, then fsck -p mount -u / mount -a swapon -a Create temporary mount points for the new filesystems (ignore /tmp unless you actually have something there to maintain - unlikely) mkdir /newroot mkdir /newusr mkdir /newvar mkdir /newhome Use dump/restore to copy the file systems cd /newroot dump -0af - / | restore -rf - cd /newusr dump -0af - /usr | restore -rf - cd /newvar dump -0af - /var | restore -rf - cd /newhome dump -0af - /home | restore -rf - These can take a while, especially the /home dump/restore if it is large. Once you are finished with this you need to fix up the /etc/fstab file on /newroot. After this, when you reboot, as long as ad0 is in front of ad4 in the BIOS boot sequence, the system will attempt to boot from ad0. Since there are more than one bootable disks now on the machine, it should give you a menu of bootable slices from which you can select. Have fun, jerry > > -- > -Chris > __
Re: Copying a FreeBSD install to a smaller disk
On Fri, 12 Sep 2008 04:55:36 +0300, Giorgos Keramidas <[EMAIL PROTECTED]> wrote: > [8] The final step was to chroot [...] > [9] Finally, I checked the new `/etc/fstab' [...] Heh! Adding `one last "final" step' didn't really work very well in this case. I should have read the long message another time before hitting `send'. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: Copying a FreeBSD install to a smaller disk
On Thu, 11 Sep 2008 17:19:55 -0700, "Chris Weiss" <[EMAIL PROTECTED]> wrote: > How would I go about copying an existing FreeBSD installation to a smaller > disk? > > I've got a 3rd FreeBSD install I can boot from and store temporary > files on, all the disks are in the same hardware, so there's no > reconfiguration other than the boot device name and interface (IE > -SATA ad4 will become IDE ad0). The disk is partitioned using the > "default" sysinstall values and the contents of the larger disk will > fit on the smaller disk, although I need to increase the size of the / > and /var slices on the target to hold everything (/usr is fairly > empty, so it'll easily fit on the smaller disk). > > For now, we'll say ad0 = new smaller disk, ad4 = boot BSD disk, and > ad6 = the BSD install I want to clone. > > The path I've been going down is to manually partition and slice ad0 > create ad4/mnt/source and ad4/mnt/target and mount /var, /tmp, etc > from ad0 and ad6 and manually copy the files. But I'm stuck on how to > handle /, since it'll have dev and proc and such. Hi Chris, If all you want is to make ad0 bootable, you don't need the *contents* of the /dev and /proc file systems. They are dynamically generated by the kernel when you mount these file systems and access them. If the used disk space in ad6 (the clone source drive) is less than the size of the clone target, it should be possible to copy the source files using any of: * tar * dump & restore * cpio Some care must be taken to avoid copying special file systems, like /dev and /proc that you mentioned. If you use something like a Live CD-ROM to boot, instead of booting from the 'source' disk, this should be easy, because the special /dev and /proc file systems will be mounted only for the *boot* device (the CD-ROM in this case), so the hard disk partitions will merely include empty directories as `potential mount-points' for the /dev, /proc and other special places. FWIW, the steps I followed when I cloned my old laptop installation to a new hard disk are the ones shown below. I didn't want to open the laptop, because that would violate its guarantee terms. So I kept the 'target' disk as ad0 and used a USB-attached enclosure for 2.5" hard disks to attach the original 'source' disk (taken out of my old, dead laptop). [1] Boot from CD-ROM using a FreeSBIE installation(*). (*) Many thanks to the FreeSBIE folks, for making such an easy to use Live CD-ROM. I have found it very useful far too many times to mention all of them in an email post! [2] Create an /mnt/source and /mnt/target directory. # mkdir -p /mnt/source # mkdir -p /mnt/target [3] Mount the source root partition, and then use the existing mount points under that source tree to mount the target partitions: # mount -o ro /dev/da0s1a /mnt/source # mount -o ro /dev/da0s1e /mnt/source/home Note that, for extra safety, I mounted the source partitions as read-only. This way I would at least get a warning if I botched the copying process, and avoid messing my original 'source' data. [4] Partition and mount the target disk (the internal ad0 disk of the laptop). This is where booting from a Live CD-ROM helped a lot, because I didn't have to do anything special to 'resize' or 'keep' parts of the disk unpartitioned. I could use the *full* disk for the new installation. # fdisk -BI /dev/ad0 # bsdlabel -w -B /dev/ad0s1 # bsdlabel -e /dev/ad0s1 When I had configured the new ad0s1a and ad0s1e partitions, I saved the label and exited bsdlabel's editor. [5] Format the target partitions: # newfs -L MYROOT /dev/ad0s1a # newfs -L MYHOME -U /dev/ad0s1e The -L labels are entirely optional, and, as you can see, I only enabled softupdates on the new /home partition. [6] Mount the target partitions under `/mnt/target'. The mounts were read-write this time: # mount /dev/ad0s1a /mnt/target # mkdir /mnt/target/home # mount /dev/ad0s1e /mnt/target/home Note that the second command is not optional. The new root file system was brand new, so it appears completely empty after being mounted. [7] Copy everything using BSD tar(1): # tar -C /mnt/source -cf - . | tar -C /mnt/target xvf - [8] The final step was to chroot into the new 'target' system, and fix-up any special directory permissions, by using the mtree(8) specifications from `/etc/mtree'. This restores any special flags like `noschg' or the permissions required for proper daemon operation in `/var/run' and so on. To avoid side-effects from the runtime environment of the shell I was using `outside' of the chroot, I cleared all environment variables, and manually set only the bare minimum of stuff I needed `inside' the chroot: # env -i USER='root' SHELL='/bin/csh' HOME='/root' \ PATH='/bin:/sbin
Copying a FreeBSD install to a smaller disk
How would I go about copying an existing FreeBSD installation to a smaller disk? I've got a 3rd FreeBSD install I can boot from and store temporary files on, all the disks are in the same hardware, so there's no reconfiguration other than the boot device name and interface (IE -SATA ad4 will become IDE ad0). The disk is partitioned using the "default" sysinstall values and the contents of the larger disk will fit on the smaller disk, although I need to increase the size of the / and /var slices on the target to hold everything (/usr is fairly empty, so it'll easily fit on the smaller disk). For now, we'll say ad0 = new smaller disk, ad4 = boot BSD disk, and ad6 = the BSD install I want to clone. The path I've been going down is to manually partition and slice ad0 create ad4/mnt/source and ad4/mnt/target and mount /var, /tmp, etc from ad0 and ad6 and manually copy the files. But I'm stuck on how to handle /, since it'll have dev and proc and such. Any thoughts on how to do this, or on a completely different approach? I'm not aware of any 3rd party tools that'll deal with shrinking FreeBSD partitions. Thanks in advance for any help you folks can give! -- -Chris ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
