RESIZE_FFS(8) | System Manager's Manual | RESIZE_FFS(8) |
resize_ffs
—
resize a file system on disk or in a file
resize_ffs |
[-cpvy ] [-s
size] special |
resize_ffs
resizes a file system.
special is the name of the raw disk device or file
where the file system resides. resize_ffs
can both
grow and shrink file systems. When growing, the disk device must of course
be large enough to contain the new file system;
resize_ffs
simply extends the file system data
structures into the new space. When shrinking,
resize_ffs
assumes this.
resize_ffs
has to copy anything that currently
resides in the space being shrunk away; there must be enough space free on
the file system for this to succeed. If there is not,
resize_ffs
will complain and exit; when this
happens, it attempts to always leave the file system in a consistent state,
but it is probably a good idea to check the file system with
fsck(8).
If no -s
option is provided,
resize_ffs
will grow the file system to the
underlying device size which is determined from
special.
The options are as follows:
-c
-p
-s
-v
-y
resize_ffs
.Interrupting
resize_ffs
may leave your file
system in an inconsistent state and require a
restore from
backup. It attempts to write in the proper order to avoid problems,
but as it is still considered experimental, you should take great care when
using it.
When resize_ffs
is applied to a consistent
file system, it should always produce a consistent file system; if the file
system is not consistent to start with, resize_ffs
may misbehave, anything from dumping core to completely curdling the data.
It is probably wise to fsck(8)
the file system before and after, just to be safe. You should be aware that
just because fsck(8) is happy
with the file system does not mean it is intact.
resize_ffs
exits with 0 on success. Any
major problems will cause resize_ffs
to exit with
the non-zero exit(3) codes, so
as to alert any invoking program or script that human intervention is
required.
resize_ffs
/dev/vg00/rlv1
will enlarge the file system on the Logical Volume /dev/vg00/lv1 from Volume Group vg00 to the current device size.
The resize_ffs
command first appeared in
NetBSD 2.0.
der Mouse
⟨mouse@rodents.montreal.qc.ca⟩ (primary author)
Jeff Rizzo ⟨riz@NetBSD.org⟩ (Byteswapped
file system and UFS2 support)
A big bug-finding kudos goes to John Kohl for finding a significant rotational layout bug.
Can fail to shrink a file system when there actually is enough space, because it does not distinguish between a block allocated as a block and a block fully occupied by two or more frags. This is unlikely to occur in practice; except for pathological cases, it can happen only when the new size is extremely close to the minimum possible.
Has no intelligence whatever when it comes to allocating blocks to copy data into when shrinking.
Does not currently support shrinking FFSv2 file systems.
October 1, 2017 | NetBSD 10.99 |