differences between setup_harddisks and setup-storage

[Michael Tautschnig]

Hi Steffen,

[...]

> 
> I had to find that *even if I preserve_always* a certain partition at 
> the "end" of the disk, setup-storage would complain about it (not ending
> at a cylinder boundary: this is a RAID on a 3ware controller which would
> fake geometries anyway) - I had to backup, drop the preserve_* setting,
> and restore after installation.
> Same happened to a 7TB partition (on an Areca controller) which had to be
> created by hand previously (leaving the minimum of 34 sectors for GPT 
> information at the beginning and end): I had to workaround this (by 
> not declaring the disk at all in disk_config, and using my old manual
> setup scripts to conditionally mkfs and add the fstab line).
> 

Now quite some time has passed by since you posted this (Sorry!!) and current
setup-storage doesn't enforce this anymore, it only prints a warning (a lack of
alignment might pose problems with some other OS, at least it apparently did in
the past).

> In addition, I noticed that the new style would make partitions on "real
> disks" (no geometry translation) _smaller_ than they were before, resulting
> in a gap:
> 

For non-preserved partitions, however, current setup-storage in mainline FAI
still rounds partition sizes down to the next cylinder boundary. Because we
don't care much about $other_OS, I have now dropped this in the current
experimental tree.

> Disk /dev/sda: 164.6 GB, 164696555520 bytes
> 255 heads, 63 sectors/track, 20023 cylinders, total 321672960 sectors
> Units = sectors of 1 * 512 = 512 bytes
> Disk identifier: 0x39d139d0
> 
>    Device Boot      Start         End      Blocks   Id  System
> /dev/sda1   *          63     5237189     2618563+  83  Linux
> /dev/sda2         5237190     7325639     1044225   82  Linux swap / Solaris
> /dev/sda3         7325640     9414089     1044225   82  Linux swap / Solaris
> /dev/sda4         9414090   321669494   156127702+   f  W95 Ext'd (LBA)
> /dev/sda5         9414153    11502539     1044193+  83  Linux
> /dev/sda6        11502603    13590989     1044193+  83  Linux
> /dev/sda7        13591053    16723664     1566306   83  Linux
> /dev/sda8        16820118   321669494   152424688+  83  Linux
> 
> (note the gap between sda7 and sda8 - about 96000 sectors!)
> 
> The corresponding disk_config partition sizes didn't change for years:
> 
> disk_config sda disklabel:msdos preserve_always:8 bootable:1
> primary /               2560    ext3    rw,errors=remount-ro    createopts="-m1"
> primary swap            1024    swap    rw
> primary swap            1024    swap    rw
> logical /tmp            1024    ext3    rw,nosuid               createopts="-m0"
> logical /var            1024    ext3    rw                      createopts="-m1"
> logical /opt            1536    ext3    rw                      createopts="-m1"
> logical /scratch        1-      xfs     rw
> 
> Apparently the rounding strategy has changed... intentionally?
> 

[...]

Well, I wouldn't call it truely intentional, but as setup-storage is a rewrite
from scratch, such differences don't come absolutely unexpected. In future
releases, however, I'd hope to avoid such gaps as rounding down to cylinder
bounds has just been dropped.

Best,
Michael

-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
Url : http://lists.uni-koeln.de/pipermail/linux-fai/attachments/20091015/77650218/attachment.bin