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mount(8)
NAME
mount, umount - Mounts and unmounts file systems
SYNOPSIS
/usr/sbin/mount [-d] [-r | -u | -w] [-o argument,...] [-t [no]type]
file-system directory
/usr/sbin/mount [-el] [-t [no]type]
/usr/sbin/mount -a [-fv] [-t [no]type]
/usr/sbin/mount [-d] [-r | -u | -w] [-o argument,...] [-t [no]type]
file-system | directory
/usr/sbin/umount -a | -A -b [-fv] [-t type] [-h host]
/usr/sbin/umount [-fv] file-system... | directory...
OPTIONS
There are options for the mount and umount commands.
Options for mount:
-a Attempts to mount all the file systems described in the /etc/fstab
file. In this case, file-system and directory are taken from the
/etc/fstab file. If -t type is specified, all of the file systems in
the /etc/fstab file with that type will be mounted. Alternatively, if
type is prefixed with no, all the file systems in the /etc/fstab file
that do not have that type will be mounted. File systems are not
necessarily mounted in the order listed in the /etc/fstab file.
-d Mounts a UNIX file system (UFS) even if it has not been unmounted
cleanly or checked by fsck for consistency. Also used to mount a
CD-ROM UFS file system.
Caution
Do not employ the -d option to mount an AdvFS fileset. When an
AdvFS fileset is mounted with the -d option, AdvFS initializes the
domain transaction log. As a result, no domain recovery will occur
for previously incomplete operations (which could cause data
corruption). If you cannot mount a fileset, use the verify command.
-e Lists all mount points. Without this option, mount does not list mount
points served by either Automount or AutoFS.
-f Performs a fake mount and actually does not mount the file system. This
option is used to verify the arguments you plan to use with the mount
command.
-l Displays the value of all the file system options.
-o argument[, argument ...]
Specifies a list of comma-separated arguments. Every argument specified
is used. Some arguments are valid for all file system types, while
others apply only to a specific type. See the Options for mount -o
Arguments section that is specific to your file system type for a
description of the arguments supported by that file system.
-q Queries the device to determine which file system or file systems are
found on DVD or CD media, and thus, how that device can be mounted.
-r Mounts the specified file system with read-only access. This option is
the equivalent of the following command:
mount -o ro file-system directory
Physically write-protected and magnetic tape file systems must be
mounted with read-only access or errors will occur when access times
are updated, whether or not any explicit write is attempted. Note that
-r and -w are paired; the default is -w.
-t [no]type
Specifies the file system type. The supported file systems are as
follows:
advfs - Advanced File System (AdvFS)
ufs - UNIX File System (UFS)
nfs - Network File System (NFS)
mfs - Memory file system (RAM Disk) See mfs(8)
cdfs - ISO 9660 CD-ROM (Compact Disc Read Only Memory) File System. See
cdfs(4).
dvdfs - DVD-ROM (Digital Versatile Disk, Read-only) File System. See
dvdfs(4). This option mounts DVD-ROM disks formatted in the Universal
Disk Format (UDF).
dfs - DCE Distributed File System
efs - DCE Episode File System
fdfs - File Descriptor File System (used by streams)
ffm - File on File Mounting File System (used by streams)
procfs - Process File System (used by debuggers)
pcfs - PC File System
sysv - System V File System
See fstab(4) for a description of the valid file system types. If the
no prefix is used, all file types except the one specified are mounted.
-u Requests that the system remount a file system so that it can update
any incore data blocks for UFS and AdvFS type file systems.
If you mount a UFS file system in a cluster for read-only access, you
cannot use the -u option to update the file system to read-write
access. A UFS file system mounted for read-only access is accessible
by all cluster members; a UFS file system mounted for read-write access
is accessible only by the cluster member on which the mount request is
issued.
For CDFS, this option is used to change the attributes of a mount, such
as the version attribute. For example, CDFS is mounted noversion by
default. The following use of the -u option shows how you can change
the default:
# mount -u -o version /cdmntpnt
-v Displays a message indicating which file system is being mounted
(verbose).
-w Mounts the specified file system with read/write access. This option
is equivalent to the -o rw option. Read/write is the default access.
Options for umount:
-A Attempts to unmount all the file systems currently mounted.
-a Attempts to unmount all the file systems listed in the /etc/fstab file.
-b Broadcasts a message to all server machines in the subnetwork to remove
the client host's name from their NFS mountdtab files.
-f Performs a fast unmount operation that causes remote file systems to be
unmounted without notifying the server.
-h host
Unmounts all file systems listed in the /etc/fstab file that are
remotely mounted from host.
-a -t type
Unmounts all file systems listed in the /etc/fstab file that are of the
specified type. The -a option must be used together with the -t
option.
-v Displays a message indicating the file system is being unmounted
(verbose).
Options for mount -o Arguments
There are many arguments for the -o option; they are discussed in the
following paragraphs.
TruCluster mount - o Arguments
The following arguments are valid for TruCluster systems:
server=cluster_member_name
Enables you to specify the cluster member, identified by
cluster_member_name, that serves a given file system at startup.
This mount command option determines where the file system is first
mounted; it does not limit or determine the cluster members to which
the file system might later be relocated or fail over.
The -o server=cluster_member_name option is valid only in a cluster,
and only for the AdvFS, UFS, MFS, NFS, CDFS, and DVDFS file systems.
MFS file systems support this option in a limited fashion: the file
system is mounted only if the specified server is the local node.
For information on using this option, refer to the Distributing File
Systems Via the mount -o Command section of the Cluster Administration
manual.
server_only
Enables cluster file system partitioning. Use this option only in a
cluster. For example:
# mount -o server_only file-system
If a file system is already mounted, you cannot use this option to
update the mount status to server_only. You must first unmount the file
system and then remount it with the server_only option.
When you mount a UFS file system in a cluster for read/write access, or
when you mount an MFS file system in a cluster for read-only or
read/write access, the server_only option is used by default.
These file systems are treated as partitioned file systems. That is,
the file system is accessible for both read-only and read/write access
only by the member that mounts it. Other cluster members cannot read
from, or write to, the MFS or UFS file system. There is no remote
access; there is no failover.
If you want to mount a UFS file system for read-only access by all
cluster members, you must explicitly mount it read-only.
For information on using this option, refer to the Partitioning File
Systems section of the Cluster Administration manual.
AdvFS mount - o Arguments
The following arguments are valid for the Advanced File System (AdvFS):
adl Causes all files in the mounted fileset to use atomic-write data
logging for the duration of the mount. Unlike chfile, which activates
data logging on a file in a manner that persists across mounts and
unmounts, the data logging provided by the -o adl mount option is
temporary and lasts only for the duration of the mount. Additionally,
files using temporary -o adl data logging may be mmaped(), unlike files
that have had persistent data logging activated on them. The temporary
data logging is suspended until the last thread using the mmapped file
unmaps it. Finally, the use of chfile on a file that is using temporary
data logging causes the chfile command to override the temporary data
logging provided by the new mount and the file's I/O mode is changed
persistently according to the arguments given to the chfile command.
For more information see chfile(8).
dual
Enables an AdvFS fileset to be mounted as a domain volume even though
it has the same AdvFS domain ID as a fileset that is already mounted.
AdvFS and UFS mount - o Arguments
The following arguments are valid for the AdvFS and UFS file systems:
atimes
Flushes to disk file access time changes for reads of regular files.
(Default behavior when neither atimes or noatimes is specified.)
noatimes
Marks file access time changes made for reads of regular files in
memory, but does not flush them to disk until other file modifications
occur. This behavior does not comply with industry standards and is
used to reduce disk writes for applications with no dependencies on
file access times.
extend
Allows the file system to make use of expanded space on the underlying
storage device. The -o option can be used on the initial mount of a
file system or by way of the -u update option if the file system is
already mounted. For UFS, if you do not want to mount the file system,
or if you want to take only part of the available storage space, you
can use the extendfs command. See the extendfs(8) reference page for
more information.
There are several steps needed in order to expand a file system:
1. Make additional storage space available on the underlying storage
device (that is, a LSM volume or hardware RAID LUN).
2. For non-LSM volumes, modify the disk label to include additional
storage. See the disklabel reference page for more information.
3. Use the mount command with the extend option to allow the file
system to use the additional storage.
For an unmounted AdvFS fileset, the following is an example of volume
expansion:
# mount -o extend domain#fileset /ausr1
For a mounted AdvFS fileset, the following is an example of volume
expansion:
# mount -u -o extend domain#fileset /ausr2
For an an unmounted UFS file system, the following is an example of
volume expansion:
# mount -o extend /dev/disk/dsk0g /useref
For a mounted UFS file system, the following is an example of volume
expansion:
# mount -u -o extend /dev/disk/dsk0h /useracct
Refer to the System Administration manual for more information.
rw Allows read/write access.
ro Allows read-only access.
rq Allows read/write access.
sw Allows file system to be used as swap space.
dirty
Allows a file system to be mounted even if it was not cleanly
unmounted.
dev Allows access to block and character-special devices.
nodev
Disallows access from the file system to either block or character-
special devices.
suid
Allows set-user-ID execution.
nosuid
Prohibits set-user-ID execution.
sync
Causes all writes to be written immediately to disk as well as to the
buffer cache.
nosync
Specifies that writes may return before data is written to disk.
smsync2
Enables the alternate smooth sync policy, in which modified pages are
not written to disk until they have been dirty and idle for the
smoothsync_age time period.
By default, modified pages are flushed after they have been dirty for
the smoothsync_age time period, regardless of continued modifications
to the page. Pages that have been mapped into virtual memory will
always use this default policy, regardless of the smsync2 setting. The
default smoothsync_age period is 30 seconds, and can be modified by
editing the inittab file.
If you enable the smsync2 option on a mount point in an AdvFS domain,
the alternate smooth sync policy goes into effect for all of the
filesets in the domain.
exec
Allows binary execution.
noexec
Prohibits binary execution.
grpid
Enables new files to inherit the parent directory's group ID. This is
the default and matches BSD semantics.
nogrpid
Applies SVID 3 semantics. For example, if the parent directory's mode
bits include IS_GID, then the new file will inherit the parent's group
ID. If IS_GID is off, then it inherits the process group ID.
UFS mount - o Arguments
The following mount -o arguments are valid only for the UFS file system.
delayed
Delays synchronously flushing metadata updates to disk. Instead,
metadata (such as inode, directory, and indirect blocks) is flushed by
the sync daemon. This mount option improves performance in the
following ways:
· Multiple updates to a block are accomplished with a single write
instead of with multiple writes of the same block, which can
occur during synchronous metadata updates.
· System responsiveness improves when running metadata intensive
applications. Metadata writes to disk do not occur immediately.
CAUTION
Data might be lost if you use this option and your system crashes
before the sync daemon flushes the metadata to disk. Do not use
this option for the root (/) or /usr file systems.
You can use this option for a temporary file system, such as /tmp,
in which applications cache temporary data that is expendable.
Refer to the nodelayed option for information on disabling delayed
metadata updates.
nodelayed
Synchronously flushes metadata updates to disk. This is the default
behavior.
By default, to maintain file system consistency, UFS metadata (such as
inode, directory, and indirect blocks) is updated synchronously, which
ensures that the UFS file system is consistent at all times and no
data is lost if your system crashes. However, it can affect file
system performance. Refer to the delayed option for information on
disabling synchronous metadata updates to improve performance.
throttle
Prevents excessive asynchronous I/O from overloading the device queue,
which can affect response time for processes waiting for I/O operations
to complete. To use this argument, you must enable smooth sync.
See the EXAMPLES section for usage examples.
NFS mount - o Arguments
The following arguments are valid for NFS file system:
dev Allows access to block and character-special devices.
nodev
Disallows access from the file system to either block or character-
special devices.
rw Allows read/write access.
ro Allows read-only access.
suid
Allows set-user-ID execution.
nosuid
Prohibits set-user-ID execution.
sync
Causes all writes to be written immediately to disk as well as to the
buffer cache.
nosync
Specifies that writes may return before data is written to disk.
exec
Allows binary execution.
noexec
Prohibits binary execution.
grpid
New files inherit the parent directory's group ID. This is the default
and matches BSD's semantics.
nogrpid
SVID 3 semantics applied. For example, if the parent directory's mode
bits include IS_GID, then the new file will inherit the parent's group
ID. If IS_GID is off, then it inherits the process group ID.
bg Retries in the background, if the first mount attempt fails.
fg Retries in the foreground.
retry=n
Sets the number of mount failure retries to n.
rsize=n
Sets the read buffer size to n bytes.
wsize=n
Sets the write buffer size to n bytes.
timeo=n
Sets the initial NFS timeout period for UDP mounts to n tenths of a
second. NFS continually adjusts the timing as a function of network
response time.
maxtimo=n
Sets the maximum value, in seconds, that is allowed between request
transmissions. (UDP mounts only)
retrans=n
Sets the number of NFS retransmissions to n.
intr
Allows hard mounted file system operations to be interrupted.
nintr
Prevents hard mounted file system operations from being interrupted,
unless the thread is terminated (for example by a SIGKILL or an AST).
soft
Returns an error if the server does not respond.
hard
Retries the request until the server responds.
nfsv2
Usually, the mount command tries to use Version 3 of the NFS protocol.
If the server does not support Version 3, then the mount command
retries the mount using Version 2. Specifying -o nfsv2 forces the
mount command to use NFS Version 2. NFS Version 3 is an enhanced
version of the NFS protocol that provides 64-bit file access, as well
as features designed to improve performance and correctness.
Alternatively, you can use the vers=2 argument.
nfsv3
Tries to use Version 3 of the NFS protocol. If the server does not
support it, Version 2 is used. This is the default.
Alternatively, you can use the vers=3 argument.
proto=type
Specifies the network transport: udp or tcp.
Specify udp to use UDP as the network transport. This is supported by
all known NFS servers. UDP works best in local, fast, and reliable
environments. The mount will fail if the server does not support NFS
over UDP. The proto=udp syntax is the default.
Specify tcp to use TCP as the network transport. This is supported by
some vendors, but not all. TCP works better than UDP in high-loss,
congested networks, and is the only way to use NFS over the Internet.
The mount will fail if the server does not support NFS over TCP.
The -o tcp syntax is compatible with 4.4 BSD syntax, while the
proto=tcp syntax is compatible with Solaris 2.4 syntax.
port=n
Sets the server IP port number to the value of n. The default is to
query the portmap daemon on the server for the port number (which is
almost always 2049). This argument is useful only when the server is
not running the portmap daemon or is running multiple NFS servers.
Both of these situations are very rare.
proplist
Allows the use of extended attributes (property list) including access
control lists (ACLs) on this file system. The NFS server exporting this
file system must be running the proplistd daemon. See proplist(4),
acl(4), and proplistd(8) .
vers=n
Specifies the version of the NFS protocol. You can specify either
Version 3 or Version 2.
Usually, the mount command tries to use Version 3 of the NFS protocol.
If the server does not support Version 3, then the mount command
retries the mount using Version 2. Specifying vers=2 forces the mount
command to use NFS Version 2. NFS Version 3 is an enhanced version of
the NFS protocol that provides 64-bit file access, as well as features
designed to improve performance and correctness.
Alternatively, you can use the nfsv2 or nfsv3 argument.
For NFS, the defaults are fg, retry=10000, timeo=11, maxtimo=20, retrans=4,
hard, and intr. Defaults for rsize and wsize are set by the kernel.
The bg argument causes mount to run in the background if the server's
mountd does not respond. The mount command attempts each request retry
times before giving up. Once the file system is mounted, each NFS request
made in the kernel waits timeo tenths of a second for a response. If no
response arrives, the timeout period is multiplied by 2 and the request is
retransmitted.
When retrans retransmissions have been sent with no reply, a soft mounted
file system returns an error on the request and a hard mounted file system
retries the request at maxtimo intervals. File systems that are mounted rw
(read/write) should use the hard argument. The number of bytes in a read
or write request can be set with the rsize and wsize arguments.
Note
Using the mount command with the -t nfs option may cause it to touch
the /etc/exports file. If the/etc/exports file has been manually
created, you should ensure that it has bin:bin owner:group ownership.
NFS Update Visibility mount - o Arguments
These arguments control how quickly you see updates to a file or directory
that has been modified by another host. Increasing these values gives you
slightly better performance. Decreasing the values decreases the time it
takes for you to see modifications made on the other host. If you are the
only person modifying files under this mount point, you should increase
these values.
acdirmin=n
Holds cached directory attributes for at least n seconds.
acdirmax=n
Holds cached directory attributes for no more than n seconds. The
maximum value you can specify is 3600.
acregmin=n
Holds cached file attributes for at least n seconds.
acregmax=n
Holds cached file attributes for no more than n seconds. The maximum
value you can specify is 3600.
actimeo=n
Sets all four attributes' cache timeout values to n.
noac
Sets no attribute caching. This argument is equivalent to actimeo=0.
nocto
Sets no fresh attribute when opening a file.
The NFS update visibility argument defaults are acdirmin=30, acdirmax=60,
acregmin=3, and acregmax=60.
CDFS mount - o Arguments
The following arguments are valid for the CD-ROM File System (CDFS):
defperm
Ignores the permission bits, if present, and defaults all file and
directory permissions to the value 0555, with a zero User ID (UID,
owned by root). Files and directories recorded on an ISO 9660-formatted
file system might or might not have permission bits. This setting is a
default argument because the permissions on most existing ISO 9660-
formatted CD-ROMs do not map to the UID scheme that is used.
nodefperm
Uses the on-disk permission bits, if present. If a file or directory
is not recorded with permission bits, the default 0555 is used.
noversion
Strips off the extension (;#) from the version string if a file
recorded on an ISO 9660-formatted file system or a file system
formatted by the High Sierra Group contains a version string. File and
directory names are displayed in lowercase letters and case-insensitive
name matching is performed. Use this argument if you are mounting a
CD-ROM containing MS-DOS applications.
rrip
Uses the Rock Ridge Interchange Protocol (RRIP) extensions to ISO 9660
(if present on the file system) to provide mixed-case file names,
device special files, and other attributes for files on the file
system. This setting is a default argument. If there are no RRIP
extensions on the file system, the file system will be mounted and the
argument will be ignored.
norrip
Turns off the Rock Ridge Interchange Protocol (RRIP) extensions to ISO
9660 for files on the file system. If there are RRIP extensions on the
file system, the file system will be mounted and the extensions will be
ignored.
joliet
Uses the Microsoft Joliet formatted CD-ROM media, which provides long,
mixed-case file names.
nojoliet
Turns off Microsoft Joliet formatted CD-ROM media.
ISO9660
Uses the ISO 9660 uppercase 8.3 formatted file system. This is the
default if no other file formats are found.
verbose
Uses verbose messages in the output.
The defaults for CDFS are ro, nodev, defperm, and rrip.
CD-ROMs can contain several formats to support different platforms and
operating systems. If you know which format you require (RRIP, Joliet, or
ISO9660) specify the appropriate qualifier to the -o option.
If you do not specify options for file name formats on the command line,
the mount command automatically tests for the presence of formats and
mounts it by default, according to the following rules of precedence:
rrip
Check if Rock Ridge Interchange Protocol (RRIP) extensions are found on
the CD-ROM, if yes, mount as -t cdfs -o rrip.
joliet
If RRIP extensions are not found, check if the media has Microsoft
Joliet formatted file names. If yes, mount as -t cdfs -o joliet.
ISO9660
If neither of the above were found, the mount command defaults to ISO
9660 format.
If you specify one or more exclusive qualifiers, such as -o norrip, the
mount command does not test for the presence of that format, and defaults
to the next highest precedent.
If a specifically-requested format is not found and other formats are not
excluded, the mount command will attempt to mount the next highest
precedent. For example, you attempt to mount a CD-ROM specifying -o joliet
format but the CD-ROM does not contain that format. Unless you
specifically requested -o norrip, the mount command will attempt to mount
RRIP. If RRIP is not found, the mount command defaults to ISO 9660 format.
FFM mount - o Arguments
The following arguments are valid for the File-on-File-Mounting (FFM) file
system:
clone
Allows two separate files to have identical contents, separate names,
and separate file descriptors. (Do not confuse this clone with an
AdvFS clone fileset.)
OPERANDS
file-system
Specifies one or more file systems. How you specify a file system
depends on whether it is UFS or NFS or AdvFS.
To specify a UFS file system, enter the name of its block device
special file. For example: /dev/disk/dsk3c. The mount command returns
an error if you try to mount the file system on a partition that is
already in use.
To specify an NFS file system, specify the host and path name in either
of these formats: host:path or path@host.
To specify an AdvFS fileset, enter the name of the file domain, a
pound-sign(#) character, and the name of the fileset. For example:
root_domain#root.
directory
Specifies one or more directories. The directory must exist before you
use the mount command. When the command is successful, the directory
becomes the name of the newly mounted root directory, its mount point.
When specified with the umount command, the directory must not be in
use. Use the pwd command to check your present working directory. If
you or another user is in the mounted directory or in any directory in
its hierarchy, you must switch to a different directory. Likewise, if
you are using files in the mounted directory, you must close the files
to successfully unmount the directory.
DESCRIPTION
Use the mount command to make a file system available for use, or mounted.
Use the umount command to make a file system unavailable for use, or
unmounted.
Use the mount command with the -q option to determine which file system or
file systems are found on an unmounted CD or DVD device. You can either
read the command output or interpret the exit code to determine which file
system is found, and thus, how it should be mounted.
The format used in the mount command determines the format returned by the
getfsstat and getmntinfo commands.
If the mount command is invoked with only a file-system or directory
operand specified, the command searches the /etc/fstab file for an entry
whose file-system or directory field matches the argument specified with
the command.
For example, if the line /dev/disk/dsk0g /usr ufs rw 1 1 is specified in
the /etc/fstab file, both of these two commands, mount /usr and mount
/dev/disk/dsk0g are equivalent to the following command:
# mount /dev/disk/dsk0g /usr
The umount command announces to the system that the file system file-system
previously mounted on directory should be removed. Either the file system
name or the directory mount point can be specified in the command line.
To use the mount and unmount commands, you must be the root user, with the
following exceptions:
· If NFS file systems have been explicitly exported to allow nonroot
users to mount the file system. Refer to the -n option of mountd(8)
for more information.
· If a CD-ROM is mounted (by specifying the -t cdfs option) and the user
owns the mount point.
The mount command also lets you mount an ISO 9660- or HSG-formatted file
system onto a directory.
No more than one user at a time should mount a disk partition with
read/write access or the file system might become corrupted.
If the directory on which a file system is to be mounted is a symbolic
link, the file system is mounted on the directory to which the symbolic
link refers, rather than on top of the symbolic link itself.
When you boot to single-user mode, the root file system is mounted with
read-only access. If you want to modify a file, you must change the options
on the root file system to read/write. You can do this with the following
command:
# mount -u /
If your /etc/fstab file is corrupted, you can mount the root file system
with the following command:
# mount -u /dev/disk/dsk??/
You must be the root user to mount a UFS file system. By default, the
maximum number of UFS mounts is 1,000. However, you can modify this value
by using the sysconfig command. For example:
# sysconfig -r vfs max-ufs-mounts=1100
The default for CDFS is to not allow access to device special files
(argument nodev) because the device numbers recorded on a disc using RRIP
extensions might not match the device numbers used by the operating system.
If you want to allow device access, mount the file system with the dev
argument and use the cddevsuppl command to map the device numbers of the
device special files on the disc to new device numbers used by the
operating system.
The mount command attempts to dynamically load the cdfs kernel modules if
they are not statically built into the running kernel. However, you must be
the root user to dynamically load the cdfs kernel modules. Other users
receive the following error should they attempt the operation:
mount: super user privileges required to load cdfs module
All other errors that could occur as the cdfs kernel modules are being
dynamically loaded produce the following error message:
mount: Can't load cdfs module
Refer to cdfs(4) for information on the correct system configuration
options to set before using CDFS.
NFS mounts can fail due to authentication requirements on the server. For
example, a "Client credential too weak" message is returned if a user
attempts to mount and the server only allows root user mounting. A "Server
rejected credential" message is returned if the server is not able to
resolve the client's IP address.
If your workstation has multiple network interfaces, the server must be
able to resolve all IP addresses from which it might receive mount
requests. See mountd(8) or the Network Administration: Services manual for
more information.
When you mount the first fileset in an AdvFS domain, AdvFS determines
whether or not it can access all data in all volumes of that domain. If
AdvFS determines that the size of any volume in the domain is actually
smaller than the size recorded for that volume in the domain's metadata,
there are two possible outcomes:
1. The mount succeeds, but in read-only mode. In this case, AdvFS is
able to read the last currently in-use block on the volume. A message
similar to the following is displayed:
Actual size of virtual disk /dev/vol/vol01 is 100352 blocks
but recorded size is 102400 blocks.
Mounting fileset staff#grads in read-only mode.
2. The mount fails. In this case, AdvFS cannot read the last currently
in-use block on the volume. A message similar to the following is
displayed:
Actual size of virtual disk /dev/vol/vol01 is 100352 blocks
but recorded size is 102400 blocks.
Cannot read essential data on /dev/vol/vol01.
Corrupted volume found; failing mount of staff#grads.
staff#grads on /grads: I/O error
When you attempt to mount an AdvFS fileset in an AdvFS domain, the number
of volumes pointed to by the /etc/fdmns/dmn_name links must equal the
number of volumes in the domain. If you attempt to mount an AdvFS file
system with an incorrect number of volumes, the following message will
appear on the console:
# Volume count mismatch for domain dmn_name.
dmn_name expects 2 volumes, /etc/fdmns/dmn_name has 1 links.
To correct the problem, you must match the number of volumes and then mount
them. See advscan(8) for more information.
Smoothsync
Smoothsync increases efficiency in the part of the file system that uses
the disks for writing dirty pages. Prior to smoothsync, dirty pages were
scheduled for writing every 30 seconds by the update daemon. The
smoothsync model schedules each page for writing after that page has been
dirty for the smoothsync_age period (default 30 seconds). This allows all
buffers to age the full smoothsync_age period, versus an average of 15
seconds with the update daemon model. This approach also distributes the
requests made of the disk subsystem evenly across the smoothsync_age
period. The update daemon model submits all the I/O requests together.
The smoothsync_age period can be set using sysconfig. A value of 0
disables smoothsync.
An alternate smoothsync policy can be enabled on a file system basis by
mounting with the smsync2 flag. With this policy, a page is not scheduled
for writing until it is dirty and unmodified for the last smoothsync_age
period. For example, suppose you have an application that keeps updating
the same page repeatedly. With smsync2 enabled, until the page has been
idle (unchanged) in memory for the entire smoothsync_age period, it will
not be written to disk. Therefore, if the smoothsync_age is 30 seconds, and
your application updates the page in memory every 10 seconds, the page
might not be written to disk for a very long time.
While this policy might further decrease I/O load, it is appropriate only
for file systems or applications in which additional data loss is
acceptable if the system crashes.
RESTRICTIONS
The mount and umount commands support mount point argument pathnames of up
to MNAMELEN, which includes the null terminating character. MNAMELEN can
be up to 90 characters long, including the null terminating character.
Before you can use the FFM file system, you must configure the kernel
option FFM_FS into the kernel.
EXIT STATUS
Standard Usage
0 (Zero)
Success.
1 An error occurred.
Query Option
Use the following chart to determine which file systems are on the device
from the exit code when you invoke the mount command with the -q option.
_____________________________
UFS CDFS DVDFS
_____________________________
0
1 X
2 X
3 X X
4 X
5 X X
6 X X
7 X X X
_____________________________
ERRORS
The following sections describe some warnings and errors produced by the
command.
Overlapping Partitions Warnings
The following warning messages about overlapping partitions are displayed
only if you use the -v option.
· Warning: partition special-device and overlapping partition(s) are
marked in use in the disklabel.
Explanation:
The specified partition overlaps with another partition or partitions
that have the fstype field set.
· Warning: partition(s) which overlap special-device are marked in use
in the disklabel.
Explanation:
The partition overlaps another partition or partitions that have the
fstype field set.
· Warning: the disklabel for special-device does not exist or is
corrupted.
Explanation:
The device specified either does not have a disk label or the disk
label has been corrupted.
· Warning: unable to check special-device against active AdvFS domains
because the directory /etc/fdmns seems to be missing or wrong.
Explanation:
There was a failure when checking the overlap with AdvFS domains. The
failure is with /etc/fdmns or /etc/fdmns/dom, or an active domain does
not exist.
· Warning: unable to check special-device against active swap devices
because special swap files are missing.
Explanation:
A failure occurred when checking the overlap with active swap devices.
The special device files associated with active swap devices are
invalid.
· Warning: unknown overlap condition errno encountered for
partitionspecial-device.
Explanation:
An unknown overlap condition was encountered for the specified device.
· Error: partition special-device is marked 'unused'
Explanation:
The fstype in the disk label temporarily is set and will revert with
the following messages when you unmount the file using umount:
Warning: partition /dev/disk/dsk5c was detected as marked unused.
Warning: partition /dev/disk/dsk5c temporarily set to /
'FS_BSDFFS' 4.2BSD Fast File System.
Warning: Please use disklabel to correct this condition.
Overlapping Partitions Errors
The following are fatal error messages associated with overlapping
partitions.
· Error: File system type fstype is invalid or not installed.
Explanation:
The file system type specified is not resident in the kernel or is
otherwise inaccessible.
· Error: an overlapping partition is open.
Explanation:
A partition that overlaps the specified partition is open.
· Error: special-device is an invalid device or cannot be opened.
Explanation:
The specified device is invalid and an overlapping partition is open.
· Error: special-device contains a fstype file system.
Explanation:
The specified partition and overlapping partitions have the fstype
field set.
· Error: Unknown severe error errno encountered for partitionspecial-
device.
Explanation:
An unknown overlap condition was encountered for the specified device.
EXAMPLES
1. To mount a local disk, enter:
% mount /dev/disk/dsk0g /usr
2. To mount an AdvFS fileset, enter either of the following commands:
% mount -t advfs usr_dmn#user1 /usr/user1
% mount usr_dmn#user1 /usr/user1
3. To mount all ufs file systems, enter:
% mount -at ufs
4. To mount a remote file system, enter either of the following commands:
% mount -t nfs serv:/usr/src /usr/src
% mount -t nfs /usr/src@serv /usr/src
5. To mount a remote file system with a hard mount, enter:
% mount -o hard serv:/usr/src /usr/src
6. To mount an ISO 9660-formatted or HSG-formatted file system from block
device /dev/disk/cdrom3c onto the local directory /cdfs with the file
version strings stripped off, enter either of the following commands:
% mount -t cdfs -o noversion /dev/disk/cdrom3c /cdfs
% mount -o noversion /dev/disk/cdrom3c /cdfs
7. To mount a UFS CD-ROM (for example, the installation CD-ROM) from
block device /dev/disk/cdrom3c onto the local directory cdrom, enter
either of the following commands:
% mount -r /dev/disk/cdrom3c /cdrom
% mount -o ro /dev/disk/cdrom3c /cdrom
8. To mount the joliet-formatted file system on a multi-formatted file
system from block device /dev/disk/cdrom3c onto the local directory
/cdfs enter the following:
% mount -t cdfs -o joliet /dev/disk/cdrom3c /cdfs
9. To unmount the file system mounted on the /mnt local directory, enter
the following command:
% umount /mnt
10. To unmount all NFS file systems, enter the following command:
% umount -A -t nfs
11. To unmount all file systems exported from host2, enter the following
command:
% umount -h host2
12. To use the delayed metadata option, use commands similar to the
following examples:
· To enable delayed metadata updates and improve performance (at
the risk of data loss), use a command similar to the following:
# mount -o delayed /dev/disk/dsk3c /tmp_files
To enable delayed metadata update on a file system that is
already mounted, use a command similar to the following:
# mount -u -o delayed /tmp_files
Any options that were in force are turned off by this command.
Therefore, you must also reenter all required mount options when
you use the -o delayed option on a mounted file system
· To disable the delayed metadata update option, use a command
similar to the following:
# mount -u -o nodelayed /tmp_files
Any options that were in force are turned off by this command.
Therefore, you must also reenter all required mount options when
you use the -o nodelayed option on a mounted file system.
· To view which mount option is in operation for a given file
system, use the mount command without arguments, as follows:
# mount
/dev/disk/dsk3c on /tmp_files type ufs (rw, delayed)
Note that the word delayed appears in the mount options list at
the end of the output from the mount command.
13. To determine how the device /dev/rdisk/cdrom0c can be mounted, enter
the following command:
# mount -q /dev/rdisk/cdrom0c
/dev/rdisk/cdrom0c can be mounted as: CDFS DVDFS
ENVIRONMENT VARIABLES
FILES
/usr/sbin/mount
Specifies the command path.
/usr/sbin/umount
Specifies the command path.
/etc/fstab
Contains static information about file systems.
SEE ALSO
Commands: cddevsuppl(8), extendfs(8), mfs(8), mountd(8), nfsd(8),
proplistd(8)
Functions: mount(2), mount(2sv), umount(2), umount(2sv), umount(3)
Files: advfs(4), cdfs(4), fstab(4), mountdtab(4)
System Administration, Network Administration: Services, Cluster
Administration
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