advfs - A local file system and utilities
The Advanced File System (AdvFS), the file system default on the Tru64 UNIX
operating system, features rapid crash recovery, high performance, and a
flexible structure that enables you to manage your file system while it is
on line. AdvFS is licensed with the Tru64 UNIX operating system.
A set of utilities that expands the capabilities of the AdvFS file system
is available as a separately licensed product: The AdvFS Utilities. These
utilities include capabilities such as adding volumes without reconfiguring
the directory hierarchy of the file system, cloning filesets to enable
online backup, improving system performance with domain balancing, and file
striping. A graphical user interface (GUI) that simplifies file system
management is available with the utilities.
Using journaling techniques, AdvFS provides faster crash recovery than the
UNIX File System (UFS), which implements crash recovery using the fsck
In addition to fast restarts, AdvFS ensures that file structures are
recovered consistently; extends file and fileset sizes to greater than 2
gigabytes; creates, deletes, and renames files faster than UFS; and pro-
vides enhanced local and remote backup utilities (vdump and rvdump, vre-
store and rvrestore).
By configuring AdvFS as the root file system, the preceding AdvFS features
are extended to the root file system. You can configure the AdvFS as the
root file system during system installation.
A UFS file system corresponds to a disk partition and is, therefore, lim-
ited by the size restrictions of that disk. In contrast, AdvFS filesets can
span all volumes in the domain.
AdvFS File System Concepts
AdvFS introduces file system concepts that do not exist for UFS. Under-
standing the following concepts prepares you for planning, creating, and
maintaining the AdvFS file system:
A volume is any mechanism that behaves like a UNIX block device, such
as a disk, disk partition, or logical volume that is configured with
the Logical Storage Manager (LSM).
A domain is a named set of one or more volumes that provides a shared
storage pool for one or more filesets (see filesets below).
When you create a domain using the mkfdmn command, you must specify a
domain name and one initial volume. The mkfdmn command creates a sub-
directory in the /etc/fdmns directory for each new domain. The domain
subdirectory contains a symbolic link to the initial volume.
If you have AdvFS Utilities, you can add additional volumes to an
existing domain by using the addvol utility. With each added volume,
the addvol utility creates a new symbolic link in the appropriate
domain subdirectory of the /etc/fdmns directory.
A UFS file system has exclusive use of the volume that contains it; an
AdvFS fileset can be one of several in a domain that is composed of
one or more volumes.
An Advanced File System consists of a domain with at least one fileset
that you create using the mkfset command. A fileset is a mountable
+ Clone Fileset
A clone fileset is a read-only copy of an existing fileset, which you
can mount as you do other filesets. You create a clone fileset by
using the clonefset utility. The reason you create and mount a clone
fileset is to perform an online backup of the existing fileset.
A clone fileset is a snapshot of the original fileset, capturing and
fixing the original fileset at a moment in time. Any changes you make
to the original fileset will not appear in its clone. Changes to data
in files in the original fileset will not appear in the clone. Also,
files that you remove from the original fileset will remain accessible
in the clone under the names they had when you created the clone
AdvFS Application Programming Interface
With the release of Tru64 UNIX Version 5.0, there is an application pro-
gramming interface (API) for AdvFS. Customers can use the API to build cus-
tomized backup and restore capabilities. The API consists of several base
system functions, which are described in the following reference pages:
Create a read-only copy of an active fileset
Get an AdvFS domain list
Get the AdvFS attributes of a file
Obtain a list of all the filesets in an AdvFS domain
Obtain fileset quotas for an AdvFS fileset
Remove a fileset or a clone fileset
Set AdvFS file attributes
Set fileset quotas for an AdvFS fileset
AdvFS Commands in the Base System
The following list summarizes the AdvFS commands that are included in the
Displays file system statistics. See advfsstat(8).
Locates AdvFS partitions on disks. See advscan(8).
Changes the attributes of a file. See chfile(8).
Changes the attributes of a fileset. See chfsets(8).
Changes the attributes of a volume. See chvol(8).
Makes the files in a domain more contiguous. See defragment(8).
Edits the user or group quotas. See edquota(8).
Checks and repairs corrupted AdvFS domains. See fixfdmn(8).
Creates a new domain. See mkfdmn(8).
Creates a fileset within an existing domain. See mkfset(8).
Checks for mounted AdvFS filesets. See mountlist(8).
Creates a list of files on specified filesets, including the path names
and i-numbers. See ncheck(8).
Displays formatted BMT pages. See nvbmtpg(8).
Displays formatted frag pages. See nvfragpg(8).
Displays formatted log pages. See nvlogpg(8).
Displays formatted tag pages. See nvtagpg(8).
Summarizes fileset ownership. See quot(8).
Displays disk usage and limits. See quota(1).
Checks file system quota consistency. See quotacheck(8).
Turns off user and group quotas. See quotaoff(8).
Turns on user and group quotas. See quotaon(8).
Renames an existing fileset. See renamefset(8).
Summarizes the disk usage and quotas for specified filesets. See
Removes an unused domain from AdvFS. See rmfdmn(8).
Deletes a fileset from a domain. See rmfset(8).
Recovers file data from damaged AdvFS domains. See salvage(8).
Takes a snapshot of an AdvFS domain's metadata. See savemeta(8).
Displays unformatted disk blocks. See shblk(8).
Displays frag file information. See shfragbf(8).
Displays domain attributes. See showfdmn(8).
Displays attributes for AdvFS files. See showfile(8).
Displays information about the filesets in a domain. See showfsets(8).
Moves the AdvFS log file to a different volume in a domain. See switch-
Prints the path name of a file, given the tag number. See tag2name(8).
vdf Displays disk information for AdvFS domains and filesets. See vdf(8).
Backs up filesets. See vdump(8).
Checks for and repairs file system inconsistencies. See verify(8).
Displays pages of an AdvFS file. See verify(8).
Restores files from devices written with the vdump command. See vre-
Displays a page from a storage bitmap (SBM) file. See verify(8).
The AdvFS Utilities are licensed and purchased separately from the Tru64
UNIX operating system. However, the software and the reference pages for
them are installed when you install the base system. You must activate a
Product Authorization Key to activate the Advanced File System Utilities.
Also available with the AdvFS Advanced Utilities license is support for
data management applications through the Data Management Applications Pro-
gramming Interface (DMAPI). See the DMAPI manpage for details.
The following list summarizes the AdvFS Utilities commands:
Adds a volume to an existing domain. See addvol(8).
Starts the AdvFS graphical user interface (GUI) daemon.
Balances the percentage of used space between volumes. See balance(8).
Creates a read-only copy of a fileset. See clonefset(8).
Accesses the Data Management Applications Programming Interface
(DMAPI). See dmapi(3).
Starts the AdvFS graphical user interface. See dtadvfs(8).
Runs the Logical Storage Manager Storage Administrator (LSMSA). See
Moves the location of a file within a domain. See migrate(8).
Attaches directories to a trashcan directory, which stores deleted
files. See mktrashcan(1).
Detaches a specified directory from a trashcan directory. See mktrash-
Removes a volume from an existing domain. See rmvol(8).
Shows the trashcan directory, if any, that is attached to a specified
directory. See mktrashcan(1).
Interleaves storage allocation of a file across two or more volumes
within a domain. See stripe(8).
When configuring root on AdvFS, set up one partition and one fileset in the
domain. Multiple volumes are not supported on root (except for a cluster
The following example creates a domain called accounts_dmn, which contains
dsk1c as the initial volume. The example also creates two filesets,
credit_fs and debit_fs, creates mount point directories, and mounts both
# mkfdmn /dev/disk/dsk1c accounts_dmn
# mkfset accounts_dmn credit_fs
# mkfset accounts_dmn debit_fs
# mkdir /mnt/credit /mnt/debit
# mount -t advfs accounts_dmn#credit_fs /mnt/credit
# mount -t advfs accounts_dmn#debit_fs /mnt/debit
Commands: mkdir(1), dmapi(3), mkfdmn(8), mkfset(8), mount(8)
Files: advfs_err(4,) fdmns(4)