clonefset - Creates a read-only copy of an AdvFS fileset
/usr/sbin/clonefset domain fileset clonename
Specifies the name of an existing AdvFS file domain.
Specifies the name of the original fileset that the clonefset utility
Specifies the name of the read-only fileset created by the clonefset
The clonefset utility enables you to perform online backups of active files
by making a read-only copy (clone) of an active fileset. Once you create
and mount a clone fileset, you can back up the clone using the vdump com-
mand or other supported backup utility (the dump command is not supported
by AdvFS). Note that the clonefset utility only clones AdvFS filesets; it
does not clone UFS file systems.
A clone fileset is a read-only snapshot of fileset data structures (meta-
data). When you clone a fileset, the utility copies only the structure of
the original fileset, not its data. When you modify files in the original
fileset, the file system copies the original pages to the clone fileset. In
this way, the clone fileset contents remain the same as when you first
You can create new versions of a clone fileset, but you can maintain only
one clone per fileset at a time. You cannot rename a clone fileset, but
there is a workaround. You can remove an existing clone fileset (and all
its files) by using the rmfset command, then create a new one with the new
You must be root user to clone an AdvFS fileset.
Each fileset within a domain must have a unique name of up to 31 charac-
ters. All whitespace characters (tab, new line, space, and so forth) and
the / # : * ? characters are invalid for fileset names.
The clonefset command cannot be used on filesets enabled for the Data
Management Application Programming Interface (DMAPI), since domains of
DAMPI-enabled file systems are limited to one fileset only. See the AdvFS
Administration for more information about DMAPI.
Do not create a clone fileset if the available disk space for the file
domain is less than 5 percent of the total. When a file domain runs out of
disk space, the file system loses its ability to maintain the consistency
of files within clone filesets. When the file system can no longer maintain
consistency, it displays warning messages similar to the following on the
user's terminal and to the console:
WARNING: advfs cannot copy-on-write data to a clone file.
WARNING: encountered the following error: ENO_MORE_BLKS (-1040)
WARNING: do not continue using the clone fileset.
WARNING: original file set: name=mnt, id=2c06a73f.00027192.00000001.8001
WARNING: clone file set: name=clone, id=2c06a73f.00027192.00000002.8002
WARNING: file id = 0000000a.8002
This message also appears in the
The following example creates a read-only copy of the credit_fs fileset
that resides in the accounts_dmn file domain. The clone fileset name in
this example is credit_clone1. This example also performs an online backup
and removes the clone fileset after the backup is complete:
# mkdir /mnt/credit_clone1
# clonefset accounts_dmn credit_fs credit_clone1
# mount -t advfs account_dmn#credit_clone1 /mnt/credit_clone1
# vdump /mnt/credit_clone1
# umount /mnt/credit_clone1
# rmfset account_dmn credit_clone1
Commands: tar(1), showfdmn(8), vdump(8), vrestore(8)
File Formats: advfs(4)