An important activity of a system administrator is to monitor file system use on a regular basis. There are three useful commands available for this task:
- df - Displays the number of free disk blocks
- du - Summarizes disk use
- quot - Summarizes file system ownership
Use the df command to display the amount of disk space used in file systems. This command lists the amount of used and available space and the amount of the file system’s total capacity being used.
The format for the df command is:
df -option resource
The table lists some of the more common options used with the df command.
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Partial Listing of Options for the df Command |
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|
Option |
Description |
-a |
Reports on all file systems, including those with entries in the /etc/mnttab file for which the ignore option is set |
-b |
Prints the total number of Kbytes free |
-e |
Prints only the number of files free |
-k |
Displays disk allocation in Kbytes |
-h |
Acts like the -k option, except that sizes are in a more readable format, for example, 14K, 234M, 2.7G, or 3.0T |
-l |
Reports on local file systems only |
|
-F FSType |
Specifies the file system type on which to operate. This is intended for use on unmounted file systems. |
To display the capacity of file systems, perform the command:
# df -k Filesystem kbytes used avail capacity Mounted on /dev/dsk/c0t0d0s0 849518 113485 676567 15% / /devices 0 0 0 0% /devices ctfs 0 0 0 0% /system/contract proc 0 0 0 0% /proc mnttab 0 0 0 0% /etc/mnttab swap 596608 360 596248 1% /etc/svc/volatile objfs 0 0 0 0% /system/object /dev/dsk/c0t0d0s6 3007086 2317518 629427 79% /usr fd 0 0 0 0% /dev/fd /dev/dsk/c0t0d0s3 1785654 92508 1639577 6% /var swap 596352 104 596248 1% /var/run swap 596568 320 596248 1% /tmp /dev/dsk/c0t0d0s7 424239 1046 380770 1% /export/home /dev/dsk/c1t3d0s7 3099093 3097 3065006 1% /data
The same file system displayed with the -h option would appear in human-readable format.
# df -h Filesystem size used avail capacity Mounted on /dev/dsk/c0t0d0s0 830M 111M 661M 15% / /devices 0K 0K 0K 0% /devices ctfs 0K 0K 0K 0% /system/contract proc 0K 0K 0K 0% /proc mnttab 0K 0K 0K 0% /etc/mnttab swap 583M 360K 582M 1% /etc/svc/volatile objfs 0K 0K 0K 0% /system/object /dev/dsk/c0t0d0s6 2.9G 2.2G 615M 79% /usr fd 0K 0K 0K 0% /dev/fd /dev/dsk/c0t0d0s3 1.7G 90M 1.6G 6% /var swap 582M 104K 582M 1% /var/run swap 583M 320K 582M 1% /tmp /dev/dsk/c0t0d0s7 414M 1.0M 372M 1% /export/home /dev/dsk/c1t3d0s7 3.0G 3.0M 2.9G 1% /data
The table defines the fields displayed by the df -k command.
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Fields for the df -k Command |
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|
Field |
Definition |
Filesystem |
The mounted file system |
kbytes |
The size of the file system in Kbytes (1024 bytes) |
used |
The number of Kbytes used |
avail |
The number of Kbytes available |
capacity |
The percentage of file system capacity used |
Mounted on |
The mount point |
The amount of space that is reported as used and avail is typically less than the amount of total space in the file system. A fraction of space, from 1 to 10 percent, is reserved in each file system as the minfree value.
When all of the reported space on the file system is in use, the file system capacity is displayed as 100 percent. Regular users receive the message “File System Full” and cannot continue working. The reserved space is available to the root user, who can then delete or back up files in the file system.
The df -k command can be used with the device as the resource to show available space on the device:
# df -k /dev/dsk/c0t1d0s6 Filesystem kbytes used avail capacity Mounted on /dev/dsk/c0t1d0s6 17153338 9 16810225 0% #
| Note: This command does not work on a partition without a file system, but does work on a partition with an unmounted file system. |
Use the du command to display the number of disk blocks used by directories and files. Each disk block consists of 512 bytes.
The format for the du command is:
du -options directory
The table describes the options for the du command.
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Options for the du Command |
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|
Option |
Description |
-k |
Displays disk use in Kbytes. |
-s |
Displays only the summary in 512-byte blocks. Using the s and k options together shows the summary in Kbytes. |
-a |
Displays the number of blocks used by all files in addition to directories within the specified directory hierarchy. |
To display disk usage in kilobytes, perform the command:
# cd /opt # du -k 3 ./SUNWits/Graphics-sw/xil/lib 4 ./SUNWits/Graphics-sw/xil 5 ./SUNWits/Graphics-sw 6 ./SUNWits 15 ./SUNWmlib/lib/sparcv8 15 ./SUNWmlib/lib/sparcv8plus 15 ./SUNWmlib/lib/sparcv8plus+vis 15 ./SUNWmlib/lib/sparcv8plus+vis2 15 ./SUNWmlib/lib/sparcv9 15 ./SUNWmlib/lib/sparcv9+vis 15 ./SUNWmlib/lib/sparcv9+vis2 120 ./SUNWmlib/lib 24 ./SUNWmlib/include 146 ./SUNWmlib 376 ./SUNWrtvc/bin 10 ./SUNWrtvc/examples/rtvc_capture_movie 24 ./SUNWrtvc/examples/rtvc_display 68 ./SUNWrtvc/examples/rtvc_video_conference 25 ./SUNWrtvc/examples/test 128 ./SUNWrtvc/examples 7 ./SUNWrtvc/man/man1 19 ./SUNWrtvc/man/man3 28 ./SUNWrtvc/man 533 ./SUNWrtvc 686 .
To display disk usage in human readable form, perform the command:
# du -h /opt |more 3K /opt/SUNWits/Graphics-sw/xil/lib 4K /opt/SUNWits/Graphics-sw/xil 5K /opt/SUNWits/Graphics-sw 6K /opt/SUNWits 24K /opt/SUNWmlib/include 15K /opt/SUNWmlib/lib/sparcv8 15K /opt/SUNWmlib/lib/sparcv8plus 15K /opt/SUNWmlib/lib/sparcv8plus+vis 15K /opt/SUNWmlib/lib/sparcv8plus+vis2 15K /opt/SUNWmlib/lib/sparcv9 15K /opt/SUNWmlib/lib/sparcv9+vis 15K /opt/SUNWmlib/lib/sparcv9+vis2 120K /opt/SUNWmlib/lib 146K /opt/SUNWmlib 376K /opt/SUNWrtvc/bin 10K /opt/SUNWrtvc/examples/rtvc_capture_movie 24K /opt/SUNWrtvc/examples/rtvc_display 68K /opt/SUNWrtvc/examples/rtvc_video_conference 25K /opt/SUNWrtvc/examples/test 128K /opt/SUNWrtvc/examples 7K /opt/SUNWrtvc/man/man1 19K /opt/SUNWrtvc/man/man3
To display disk usage including files, perform the command:
# du -ak /opt 1 /opt/SUNWits/Graphics-sw/xil/lib/libxil.so 1 /opt/SUNWits/Graphics-sw/xil/lib/libxil.so.1 3 /opt/SUNWits/Graphics-sw/xil/lib 4 /opt/SUNWits/Graphics-sw/xil (output removed for brevity) 19 /opt/SUNWrtvc/man/man3 1 /opt/SUNWrtvc/man/windex 28 /opt/SUNWrtvc/man 533 /opt/SUNWrtvc 686 /opt
To display only a summary of disk usage, perform the command:
# du -sk /opt 686 /opt
Use the quot command to display how much disk space, in kilobytes, is being used by users.
The format for the quot command is:
quot -options filesystemThe table describes the options for the quot command.
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Options for the quot Command |
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|
Option |
Description |
-a |
Reports on all mounted file systems |
-f |
Includes the number of files |
To display disk space being used by users on all mounted file systems, perform the command:
# quot -af
/dev/rdsk/c0t0d0s0 (/):
112410 5246 root
31 12 uucp
11 11 lp
1 1 adm
/dev/rdsk/c0t0d0s6 (/usr):
2313692 102415 root
806 15 uucp
11 4 bin
1 1 adm
…
The columns represent kilobytes used, number of files, and owner, respectively.
To display a count of the number of files and space owned by each user for a specific file system, enter the following:
# quot -f /dev/dsk/c0t0d0s7
/dev/rdsk/c0t0d0s7 (/export/home):
9 2 root
15 35 sue
51 51 paul
23 25 jeff
The Solaris Management Console Usage Tool provides a graphical display of the available space for all mounted file systems.
To use the Solaris Management Console storage Usage Tool, launch the Solaris Management Console by typing smc& at a command line, or select it from the Application Manager Window. To locate the Usage Tool, select This Computer, then select Storage, then select Mounts and Shares on the Solaris Management Console.
The image shows the Management Tools: Solaris Management Console window with the disk usage information.
