NAME¶
growfs —
grow size of an existing ufs
file system
SYNOPSIS¶
growfs |
[-Ny]
[-s size]
special |
DESCRIPTION¶
The
growfs utility extends the
newfs(8)
program. Before starting
growfs the disk must be labeled to
a bigger size using
bsdlabel(8). If you wish to grow a file
system beyond the boundary of the slice it resides in, you must re-size the
slice using
fdisk(8) before running
growfs. If you are using volumes you must enlarge them by
using
vinum(8). The
growfs utility extends
the size of the file system on the specified special file. Currently
growfs can only enlarge unmounted file systems. Do not try
enlarging a mounted file system, your system may panic and you will not be
able to use the file system any longer. Most of the
newfs(8)
options cannot be changed by
growfs. In fact, you can only
increase the size of the file system. Use
tunefs(8) for
other changes.
The following options are available:
- -N
- “Test mode”. Causes the new file system
parameters to be printed out without actually enlarging the file
system.
- -y
- “Expert mode”. Usually growfs
will ask you if you took a backup of your data before and will do some
tests whether special is currently mounted or
whether there are any active snapshots on the file system specified. This
will be suppressed. So use this option with great care!
- -s
size
- Determines the size of the file
system after enlarging in sectors. This value defaults to the size of the
raw partition specified in special (in other words,
growfs will enlarge the file system to the size of the
entire partition).
EXAMPLES¶
growfs -s 4194304
/dev/vinum/testvol
will enlarge
/dev/vinum/testvol up to 2GB if there is enough
space in
/dev/vinum/testvol.
SEE ALSO¶
bsdlabel(8),
dumpfs(8),
fdisk(8),
ffsinfo(8),
fsck(8),
newfs(8),
tunefs(8),
vinum(8)
HISTORY¶
The
growfs utility first appeared in
FreeBSD
4.4.
AUTHORS¶
Christoph Herrmann ⟨chm@FreeBSD.org⟩
Thomas-Henning von Kamptz
⟨tomsoft@FreeBSD.org⟩
The GROWFS team ⟨growfs@Tomsoft.COM⟩
BUGS¶
The
growfs utility works starting with
FreeBSD 3.x. There may be cases on
FreeBSD 3.x only, when
growfs does
not recognize properly whether or not the file system is mounted and exits
with an error message. Then please use
growfs
-y if you are sure that the file system is not mounted. It
is also recommended to always use
fsck(8) after enlarging
(just to be on the safe side).
For enlarging beyond certain limits, it is essential to have some free blocks
available in the first cylinder group. If that space is not available in the
first cylinder group, a critical data structure has to be relocated into one
of the new available cylinder groups. On
FreeBSD 3.x
this will cause problems with
fsck(8) afterwards. So
fsck(8) needs to be patched if you want to use
growfs for
FreeBSD 3.x. This patch
is already integrated in
FreeBSD starting with
FreeBSD 4.4. To avoid an unexpected relocation of that
structure it is possible to use
ffsinfo -g
0 -l 4 on the
first cylinder group to verify that
nbfree in the CYLINDER
SUMMARY (internal cs) of the CYLINDER GROUP
cgr0 has enough
blocks. As a rule of thumb for default file system parameters one block is
needed for every 2 GB of total file system size.
Normally
growfs writes this critical structure to disk and
reads it again later for doing more updates. This read operation will provide
unexpected data when using
-N. Therefore, this part cannot
really be simulated and will be skipped in test mode.