To create a 20-MiByte Reiser file system file (on a SuSE 9.0 system), do
something like this.
root@shark# dd if=/dev/zero of=reiser1.img count=40960
40960+0 records in
40960+0 records out
root@shark# ls -l reiser1.img
-rw-r--r-- 1 root root 20971520 Nov 17 19:16 reiser1.img
root@shark# losetup /dev/loop3 reiser1.img
root@shark# losetup /dev/loop3
/dev/loop3: [0700]:109 (reiser1.img) offset 0, no encryption
root@shark# mkfs.reiserfs /dev/loop3
mkfs.reiserfs 3.6.9 (2003 www.namesys.com)
A pair of credits:
Vitaly Fertman wrote fsck for V3 and maintains the reiserfsprogs package now.
He wrote librepair, userspace plugins repair code, fsck for V4, and worked on
developing libreiser4 and userspace plugins with Umka.
Alexander Lyamin keeps our hardware running, and was very generous to our
project in many little ways.
Guessing about desired format.. Kernel 2.4.21-215-default is running.
reiserfs_create_journal: cannot create a journal of 8193 blocks with 18 offset
on 5120 blocks
Hmmm. I guess this means I need a bigger file to mount on. Here's the built-in
Reiser 3.6.9 manual.
root@shark# mkfs.reiserfs
Usage: mkfs.reiserfs [options] device [block-count]
Options:
-b | --block-size N size of file-system block, in bytes
-j | --journal-device FILE path to separate device to hold journal
-s | --journal-size N size of the journal in blocks
-o | --journal-offset N offset of the journal from the start of
the separate device, in blocks
-t | --transaction-max-size N maximal size of transaction, in blocks
-h | --hash rupasov|tea|r5 hash function to use by default
-u | --uuid UUID store UUID in the superblock
-l | --label LABEL store LABEL in the superblock
--format 3.5|3.6 old 3.5 format or newer 3.6
-f | --force specified once, make mkreiserfs the whole
disk, not block device or mounted partition;
specified twice, do not ask for confirmation
-q | --quiet quiet work without messages, progress and
questions. Useful if run in a script. For use
by end users only.
-d | --debug print debugging information during mkreiser
-V print version and exit
Maybe I could reduce the journal size. But instead I'll just make the file
bigger. Here we go again...
root@shark# dd if=/dev/zero of=reiser1.img count=204800
204800+0 records in
204800+0 records out
root@shark# ls -l reiser1.img
-rw-r--r-- 1 root root 104857600 Nov 17 19:52 reiser1.img
root@shark# losetup /dev/loop3 reiser1.img
root@shark# losetup /dev/loop3
/dev/loop3: [0700]:109 (reiser1.img) offset 0, no encryption
root@shark# mkfs.reiserfs /dev/loop3
mkfs.reiserfs 3.6.9 (2003 www.namesys.com)
A pair of credits:
Edward Shushkin wrote the encryption and compression file plugins, and the V3
journal relocation code.
Vladimir Demidov wrote the parser for sys_reiser4(), the V3 alpha port, part of
the V3 journal relocation code, and helped Hans keep the business side of
things running.
Guessing about desired format.. Kernel 2.4.21-215-default is running.
Format 3.6 with standard journal
Count of blocks on the device: 25600
Number of blocks consumed by mkreiserfs formatting process: 8212
Blocksize: 4096
Hash function used to sort names: "r5"
Journal Size 8193 blocks (first block 18)
Journal Max transaction length 1024
inode generation number: 0
UUID: a5387467-085a-4dea-be5a-18eddf521aea
ATTENTION: YOU SHOULD REBOOT AFTER FDISK!
ALL DATA WILL BE LOST ON '/dev/loop3'!
Continue (y/n):
Now that's more like it! I say y to this:
Continue (y/n):y
Initializing journal - 0%....20%....40%....60%....80%....100%
Syncing..ok
ReiserFS is successfully created on /dev/loop3.
Now continuing...
root@shark# mkdir reiser1
root@shark# ls -ld reiser*
drwxr-xr-x 2 root root 48 Nov 17 19:55 reiser1
-rw-r--r-- 1 root root 104857600 Nov 17 19:52 reiser1.img
root@shark# mount /dev/loop3 reiser1
root@shark# df reiser1
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/loop3 102392 32840 69552 33% /home2/rsoft/reiser1
Well, what could be simpler!!
Ironically, the file reiser1.img is itself in a file system
which is an encrypted loop-mounted Reiser file system.
The next logical step is to work out how to undo the deed.
root@shark# umount reiser1
root@shark# df reiser1
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/hdd1 156275512 24241608 132033904 16% /home2
root@shark# losetup /dev/loop3
/dev/loop3: [0700]:109 (reiser1.img) offset 0, no encryption
root@shark# losetup -d /dev/loop3
root@shark# losetup /dev/loop3
loop: can't get info on device /dev/loop3: No such device or address
Alles klar, as they say in the old country!
It's interesting to look into the formatted file.
root@shark# od -ah reiser1.img | head -20
0000000 nul nul nul nul nul nul nul nul nul nul nul nul nul nul nul nul
0000 0000 0000 0000 0000 0000 0000 0000
*
0200000 nul d nul nul l C nul nul dc3 sp nul nul dc2 nul nul nul
6400 0000 43ec 0000 2013 0000 0012 0000
0200020 nul nul nul nul nul sp nul nul nul eot nul nul ff N - `
0000 0000 2000 0000 0400 0000 ce0c 602d
0200040 eot etx nul nul rs nul nul nul nul nul nul nul nul dle L etx
0384 0000 001e 0000 0000 0000 1000 03cc
0200060 stx nul soh nul R e I s E r 2 F s nul nul nul
0002 0001 6552 7349 7245 4632 0073 0000
0200100 etx nul nul nul stx nul soh nul stx nul nul nul nul nul nul nul
0003 0000 0002 0001 0002 0000 0000 0000
0200120 soh nul nul nul % 8 t g bs Z M j > Z can m
0001 0000 38a5 6774 5a08 ea4d 5abe ed18
0200140 _ R sub j nul nul nul nul nul nul nul nul nul nul nul nul
52df ea1a 0000 0000 0000 0000 0000 0000
0200160 nul nul nul nul nul nul nul nul nul nul nul nul nul nul nul nul
0000 0000 0000 0000 0000 0000 0000 0000
*
Höchst interessant, as we used to say in the old country!!
So let's try this just once more to make sure it's all okay.
root@shark# losetup /dev/loop3 reiser1.img
root@shark# mount /dev/loop3 reiser1
root@shark# df reiser1
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/loop3 102392 32840 69552 33% /home2/rsoft/reiser1
Alles in Ordnung!
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