Re: Migrate to 3TB disk
On Fri, Sep 14, 2012 at 8:20 AM, Hendrik Boom hend...@topoi.pooq.com wrote: I have two new 3TB disks. I'm adding them to an existing Debian (stable/ squeeze AMD64) system. ... I have several questions: (1) Is there up-to-date documentation on these matters. I'd love to RTFM if only I could find the FM. I gather I need to know about: (1a) sector size and how to choose it, https://en.wikipedia.org/wiki/Advanced_Format Large modern disks use 4096 byte sectors, but most/all still report 512 (too many old OSs out there). Linux kernel higher than 2.6.31 properly reports size and alignment issues. Use 4k block size when creating the FS. Use parted/gparted/other libparted program, as it can handle GPT (which you also probably want) and automatically aligns for 4k. I got a 4k disk fairly early on, haven't had any problems, but it is just a backup disk. I used gparted to set it up, no problems. I don't have any one source for all this, just accumulation from different places. And it has been a while, so use a grain of salt. (1b) disk block numbers more than 32 bits, (1c) file and partition size limits among ext2, 3, and 4. (my6 ext3's were migrated from ext2, so they may share the limits of the original ext2fs) The man pages should cover that, or the Wikipedia pages. IMO, there are plenty of reasons to go with new Ext4 filesystems anyway. (1d) EFI Only applies with a pretty new motherboard that supports it. (1e) How this all affects booting (presumably with GRUB-2) in case I have a non-EFI BIOS (it is a somewhat old machine, having been build when SATA was just appearing on the market) Grub2 should be fine, it knows stuff like GPT (1f) Which of the utilities I'm used to will handle this large a disk with a new partitioning scheme and larger files -- things like fsck, badblocks, lvm, software RAID, rdiff-backup, grub, lilo, sqlite, etc. Id badblocks can't hacl it. for example. the full-service disk test I'm now doing may be useless. I couldn't say much about it, but I would think fsck should only care about the FS, not the underlying disk.Sqlite and such should be high enough up the stack that it wouldn't be an issue. As far as I know the kernel and filesystems and fs utilities have pretty much been updated. (1f) Whether all this would go better with wheezy instead of squeeze, and so whether I should upgrade squeeze to wheezy first. Couldn't hurt, and wheezy is getting close to release... That said, the squeeze kernel should be fine, I would mostly just double check the version of parted. (I do not remember what versions of things I was using when I did it, I run unstable on my PC) (1g) Would an up-to-date Debian installer take care of most of this stuff? It's not the way I [refer to go, because this machine is normally kept running 24 hours a day, and is actually used for much of this time. Reconfiguring a newly-installed system, instead of an upgrade, would be a pain. I do not think it is needed at all. Cheers, Kelly Clowers -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/CAFoWM=-noB=l3yk2prl+os8s0l06xgq8qtshtiej+5hugyb...@mail.gmail.com
Re: Migrate to 3TB disk
On Vi, 14 sep 12, 15:20:26, Hendrik Boom wrote: Now currently my machine has two small (750G) disks that it stores the bulk of its files on, and one tiny (250G) IDE disk that it boots from. Tiny? That's almost as big as my entire storage (2 x 160 GiB). (1c) file and partition size limits among ext2, 3, and 4. (my6 ext3's were migrated from ext2, so they may share the limits of the original ext2fs) For partitions in the TiB size you will definitely want ext4 or xfs as ext3 fsck times would be horrible. Kind regards, Andrei -- Offtopic discussions among Debian users and developers: http://lists.alioth.debian.org/mailman/listinfo/d-community-offtopic signature.asc Description: Digital signature
Re: Migrate to 3TB disk
On Fri, 14 Sep 2012 19:55:58 +0300, Andrei POPESCU wrote: On Vi, 14 sep 12, 15:20:26, Hendrik Boom wrote: Now currently my machine has two small (750G) disks that it stores the bulk of its files on, and one tiny (250G) IDE disk that it boots from. Tiny? That's almost as big as my entire storage (2 x 160 GiB). Yeah. I still remember when that was a huge disk. I even remember the time that 5 megabytes was a big hard disk. I'm just trying to keep up with the times, without resorting to terms like a very very very very large disk :) (1c) file and partition size limits among ext2, 3, and 4. (my6 ext3's were migrated from ext2, so they may share the limits of the original ext2fs) For partitions in the TiB size you will definitely want ext4 or xfs as ext3 fsck times would be horrible. Which probably means building a new file system and copying all the files. Even if it's possible to upgrade in place, it would probably mean preserving the existing low-level structure, like 512-byte sectors instead of 4K sectors. Anybody have any input as to whether ext4 or xfs would offer better long- term reliability? Kind regards, Andrei Thanks -- hendrik -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/k2vp4s$5pk$2...@ger.gmane.org
Re: Migrate to 3TB disk
On Fri, 14 Sep 2012 09:22:51 -0700, Kelly Clowers wrote: (1d) EFI Only applies with a pretty new motherboard that supports it. I was under the impression that an old BIOS (which is what I probably have) doesn't know how to understand how to understand the partition table that comes with GPT, which goes with EFI, and that therefore there had to be some kind of shim installed to bridge the difference so that it can get to grub -- some kind of bootable BIOS replacement, which may take a partition of its own, presumably with some kind of kludgy hybrid of GPT and the old partition table. I could be wrong, and my information could be out-of-date. Most of the information about large disk partitioning I find on the web worries about the 8.5GB and the 137GB limit. Thanks. -- hendrik -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/k2vq0p$5pk$3...@ger.gmane.org
Re: Migrate to 3TB disk
On Vi, 14 sep 12, 17:22:36, Hendrik Boom wrote: Which probably means building a new file system and copying all the files. Even if it's possible to upgrade in place, it would probably mean preserving the existing low-level structure, like 512-byte sectors instead of 4K sectors. There are docs about migrating ext3 to ext4. Anybody have any input as to whether ext4 or xfs would offer better long- term reliability? Both ext4 and xfs are under active development. The only contender would be btrfs, which is still considered experimental. Kind regards, Andrei -- Offtopic discussions among Debian users and developers: http://lists.alioth.debian.org/mailman/listinfo/d-community-offtopic signature.asc Description: Digital signature
Re: Migrate to 3TB disk
On 9/14/2012 3:22 PM, Andrei POPESCU wrote: On Vi, 14 sep 12, 17:22:36, Hendrik Boom wrote: Which probably means building a new file system and copying all the files. Even if it's possible to upgrade in place, it would probably mean preserving the existing low-level structure, like 512-byte sectors instead of 4K sectors. There are docs about migrating ext3 to ext4. Anybody have any input as to whether ext4 or xfs would offer better long- term reliability? There are factions devoted to each. In the short term, either would do, although I favor ext4 due to the extremely large installed base (of ext? family). I don't think it will lack for maintenance. In the long term, I foresee btrfs becoming popular, based on its feature set and potential benefits. If you are migrating from an ext? fs, it seems to make the most sense to me to go with ext4. Both ext4 and xfs are under active development. The only contender would be btrfs, which is still considered experimental. Yes. I think btrfs is not yet suitable for a system that is used heavily, as all the pieces of the puzzle are not in place yet. XFS may be more reliable according to some criteria, but according to some people, it is more likely to suffer fs corruption in the event of a power outage or hardware failure or kernel crash. This is a source of some fierce debating. ext4 is relatively new, not having been considered stable for all that long, though it *has* been several kernels ago that it was considered stable. Since before the release of Squeeze. Six of one, half a dozen of the other, I think either XFS or ext4 would be a good choice. Mark -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/5053dca7.20...@allums.com
