After you compiled and installed a new version of FreeBSD, use etcupdate(8) to merge
configuration updates.
Run "etcupdate extract" once when your sources match your running system, then run
"etcupdate" after every upgrade and "etcupdate resolve" to resolve any conflicts.
-- Lars Engels
You can prevent the removal of a ZFS snapshot by using the hold subcommand.
For example, to prevent the snapshot called milestone from deletion, run the
following command:
# zfs hold milestone_hold mypool/projects@my_milestone
The "zfs holds" command will list all current snapshots that are protected
this way (-r for a recursive list):
# zfs holds -r mypool
The TIMESTAMP column in the output of the above command is from when the
hold was created, not the snapshot it holds. The "zfs destroy" command will
echo a "dataset is busy" message on the console when it encounters a hold.
Use "zfs release" to release the hold on the snapshot:
# zfs release milestone_hold mypool/projects@my_milestone
-- Benedict Reuschling
Want colour in your directory listings? Use "ls -G". "ls -F" is also useful,
and they can be combined as "ls -FG".
Nice bash prompt: PS1='(\[$(tput md)\]\t <\w>\[$(tput me)\]) $(echo $?) \$ '
-- Mathieu
To set a quota of 10 GB for the user named foo on a ZFS dataset, run the
following command:
# zfs set userquota@foo=10G pool/home/foo
The zfs userspace command can display the quota and current space usage:
# zfs userspace pool/home/foo
To unset a quota, assign "none" as the value.
-- Benedict Reuschling
By pressing "Scroll Lock" you can use the arrow keys to scroll backward
through the console output. Press "Scroll Lock" again to turn it off.
Don't have a "Scroll Lock" key? The "Pause / Break" key acts alike.
To read a compressed file without having to first uncompress it, use
"zcat" or "zless" to view it. There is also "bzcat", "bzless", "xzcat"
and "xzless".
-- Dru
If you have a CD-ROM drive in your machine, you can make the CD-ROM that is
presently inserted available by typing 'mount /cdrom' as root. The CD-ROM
will be available under /cdrom/. Remember to do 'umount /cdrom' before
removing the CD-ROM (it will usually not be possible to remove the CD-ROM
without doing this.)
Note: This tip may not work in all configurations.
To change an environment variable in tcsh you use: setenv NAME "value"
where NAME is the name of the variable and "value" its new value.
You can press up-arrow or down-arrow to walk through a list of
previous commands in tcsh.
Handy bash(1) prompt: PS1="\u@\h \w \!$ "
-- David Scheidt
This fortune brought to you by:
$FreeBSD$
To obtain a neat PostScript rendering of a manual page, use ``-t'' switch
of the man(1) utility: ``man -t
man -t grep > grep.ps # Save the PostScript version to a file
or
man -t printf | lp # Send the PostScript directly to printer
Want to list all files of an installed package? Enter
"pkg info -l packagename".
-- Lars Engels
If you use the C shell, add the following line to the .cshrc file in your
home directory to prevent core files from being written to disk:
limit coredumpsize 0
-- Dru
If you accidentally end up inside vi, you can quit it by pressing Escape, colon
(:), q (q), bang (!) and pressing return.
To read a compressed file without having to first uncompress it, use
"zcat" or "zless" to view it. There is also "bzcat", "bzless", "xzcat"
and "xzless".
-- Dru
Do you want to know which version of FreeBSD you are running? Enter
"freebsd-version -ku" to display kernel and userland version.
-- Lars Engels
ZFS can display I/O statistics for a given pool using the iostat subcommand.
By default, it will display one line of current activity. To display stats
every 5 seconds run the following command (cancel with CTRL+C):
zpool iostat 5
To view individual disk activities, specify the -v parameter:
zpool iostat -v
Of course, both can be combined. For more options, see zpool(8).
-- Benedict Reuschling
In order to make fetch (the FreeBSD downloading tool) ask for
username/password when it encounters a password-protected web page, you can set
the environment variable HTTP_AUTH to 'basic:*'.