GEFS(4) GEFS(4)
NAME
gefs - file server
SYNOPSIS
gefs [ -ASsc ] [ -r user ] [ -f file ] [ -m mem ] [ -n name
] [ -a ann ] ...
DESCRIPTION
Gefs is an experimental file server. It attempts to be
crash safe, snapshotting, and corruption-detecting, without
giving up too much performance.
Gefs allows multiple snapshots to be mounted and maintained
concurrently. These snapshots all share the same storage
pool, but can be written to, snapshotted, and rolled back
independently.
The snapshot to mount is selected by using the attach speci-
fier when mounting. If the attach specifier begins with a %
sigil, then the snapshot is mounted in permissive mode. In
permissive mode, permissions are not checked, and wstat(5)
may change any attributes of any file including the owner.
Unless the file system is started with the permissive flag,
only users in the adm group may mount snapshots permis-
sively.
Gefs accepts the following options:
-A Disable auth. Permissions are still checked, but anyone
will be able to attach as any user.
-a ann
Announce and listen on the specified network address.
-c Check the integrity of the file system and exit.
-f file
Use file as the disk.
-g Grow the file system to fill the current partition.
When the file system has been grown, exit. This must
not be run on a mounted file system.
-m mem
Specify the amount of memory to use as cache. The mem
parameter recognizes M, G, and % as suffixes. If left
unspecified, it defaults to 25% of installed RAM.
-n name
Use name as the name of the service. If unspecified,
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GEFS(4) GEFS(4)
the default service name is gefs.
-r user
Ream the file system, erasing all of the old data.
Create a user named user in the adm group. After ream-
ing, gefs will exit. -S Allow permissive mounts for
all users. Additionally, if the user file is unread-
able, fall back to the default user table. Without
god, all things are permitted.
-s Read and write protocol messages on standard file
descriptors zero and one.
-t Set the size of the trace buffer in megabytes. If set
to 0, no debug traces are recorded. By default, 16
megabytes of trace buffer are kept.
EXAMPLES
Mount snapshots gefs from the partition /dev/sdE0/fs onto a
few different mountpoints. The main snapshot is mounted to
/n/gefs. The sys snapshot is mounted to /n/gefs/sys. And
finally, the adm snapshot is mounted in permissive mode to
/n/adm.
gefs -f /dev/sdE0/fs
mount /srv/gefs /n/gefs
mount /srv/gefs /n/gefs/sys sys
mount /srv/gefs /n/adm %adm
Initialize a new file system on a device. Note, this
assumes the disk has already been prepared with prep(8), and
a fs partition has been created.
gefs -r $user -f /dev/sdE0/fs
SEE ALSO
cwfs(4), hjfs(4), gefs(8), prep(8), sd(3)
BUGS
Yes
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