Commands tagged Debian (100)

  • Check tcp-wrapping support

    This function returns TRUE if the application supports tcp-wrapping or FALSE if not by reading the shared libraries used by this application. Show Sample Output


    1
    supportsWrap(){ ldd `which ${1}` | grep "libwrap" &>/dev/null && return 0 || return 1; }
    cicatriz · 2010-12-01 15:22:29 15
  • Check if a package is installed. If it is, the version number will be shown.

    If the first two letters are "ii", then the package is installed. You can also use wildcards. For example, . dpkg -l openoffice* . Note that dpkg will usually not report packages which are available but uninstalled. If you want to see both which versions are installed and which versions are available, use this command instead: . apt-cache policy python Show Sample Output


    1
    dpkg -l python
    hackerb9 · 2011-01-05 06:15:13 5
  • apt-get upgrade with bandwidth limit

    Trickle is here: http://monkey.org/~marius/pages/?page=trickle Trickle is a simple bandwidth limiter


    1
    trickle sudo apt-get update -y
    mrman · 2011-02-15 02:05:37 3
  • locating packages held back, such as with "aptitude hold <package>"

    locating packages held back, such as with "aptitude hold "


    1
    aptitude search ~ahold
    pykler · 2012-04-29 15:02:32 4
  • List your largest installed packages (on Debian/Ubuntu)

    The other commands were good, but they included packages that were installed and then removed. This command only shows packages that are currently installed, sorts smallest to largest, and formats the sizes to be human readable. Show Sample Output


    1
    dpkg-query --show --showformat='${Package;-50}\t${Installed-Size}\n' `aptitude --display-format '%p' search '?installed!?automatic'` | sort -k 2 -n | grep -v deinstall | awk '{printf "%.3f MB \t %s\n", $2/(1024), $1}'
    EvilDennisR · 2013-07-26 23:18:20 13
  • print the name of each package APT knows [matching a prefix]

    In this case, linux- is the prefix; simply running apt-cache pkgnames would list every package APT knows about. The default APT config assumes -g, --generate; to use the cache as/is, you could similarly run: apt-cache --no-generate pkgnames [prefix] Adding --all-names, like so: apt-cache --no-generate --all-names pkgnames [prefix] would print all the packages APT knows about, using the cache as/is, including virtual packages and missing dependencies. This command was shamelessly stolen from the apt-cache(8) man-page. Show Sample Output


    1
    apt-cache pkgnames linux-
    benjabean1 · 2014-12-14 06:48:57 8
  • Marks all manually installed deb packages as automatically installed.

    An alternative without aptitude.


    1
    apt-mark showmanual|xargs sudo apt-mark markauto
    DellDor · 2015-08-10 02:35:22 12
  • Remove specific versions of old kernels (Ubuntu/Debian)

    If, for example, you want to remove all kernels and headers but the last three versions, you can't use one of that magic all-in-one "remove old stuff" commands. With this simple but elegant command you can remove a range of versions, or a list of versions with e.g. {14,16,20}. Show Sample Output


    1
    apt purge linux*{14..18}*
    ppq · 2016-04-20 07:44:55 11
  • Find name of package which installed a given shell command

    Some command names are very different from the name of the package that installed them. Sometimes, you may want to find out the name of the package that provided a command on a system, so that you can install it on another system. Show Sample Output


    1
    dpkg -S "$(readlink -e $(which w))" | cut -d ':' -f 1
    Fox · 2016-05-18 09:41:29 11
  • get a rough estimate about how much disk space is used by all the currently installed debian packages

    The vaule is expressed in megabytes Show Sample Output


    1
    echo $[ ($(dpkg-query -s $(dpkg --get-selections | grep -oP '^.*(?=\binstall)') | grep -oP '(?<=Installed-Size: )\d+' | tr '\n' '+' | sed 's/+$//')) / 1024 ]
    acavagni · 2019-06-02 16:35:34 55
  • find packages installed from e.g. sid which are newer than those available from e.g. testing when sid is no longer present as a source repo

    This is useful if you add sid, install some packages, then remove sid and want to work out which packages you installed from sid that should be removed (e.g. before an upgrade to the new stable). Alternatively you can think of this as "find installed packages that can no longer be installed."


    1
    aptitude search -F '%p %v %V %O' '?narrow(?not(?archive("^[^n][^o].*$")),?version(CURRENT))' | while IFS=' ' read -r pkg ver candidate origin; do if [[ $ver == "$candidate" ]] && [[ $origin == '(installed locally)' ]]; then echo "$pkg"; fi; done
    sorpigal · 2021-12-26 15:57:15 304
  • find files in $PATH that were not installed through dpkg

    OS: Debian based (or those that use dpkg) Equivalent to doing a dpkg -S on each file in $PATH, but way faster. May report files generated though postinstall scripts and such. For example . It will report /usr/bin/vim .. which is not not a file installed directly by dpkg, but a link generated by alternatives hooks


    0
    echo -e "${PATH//://\n}" >/tmp/allpath; grep -Fh -f /tmp/allpath /var/lib/dpkg/info/*.list|grep -vxh -f /tmp/allpath >/tmp/installedinpath ; find ${PATH//:/ } |grep -Fxv -f /tmp/installedinpath
    kamathln · 2009-09-09 05:33:14 4
  • List your largest installed packages (on Debian/Ubuntu)

    List packages and their disk usage in decreasing order. This uses the "Installed-Size" from the package metadata. It may differ from the actual used space, because e.g. data files (think of databases) or log files may take additional space. Show Sample Output


    0
    perl -ne '$pkg=$1 if m/^Package: (.*)/; print "$1\t$pkg\n" if m/^Installed-Size: (.*)/;' < /var/lib/dpkg/status | sort -rn | less
    hfs · 2009-10-19 12:55:59 7
  • Show a Package Version on Debian based distribution


    0
    dpkg-query -W -f='${Version}' package-name
    ohe · 2010-06-02 14:39:08 3
  • Show a Package Version on Debian based distribution

    Supports regex pattern and very flexible output parameters and search options. Show Sample Output


    0
    aptitude -F '%p %v#' search <pattern>
    unixmonkey10157 · 2010-06-03 15:37:27 3
  • A better 'apt-cache' using Xapian to rank results

    A replacement for 'apt-cache' that uses a Xapian to produce ranked results. Available in 'apt-xapian-index' 0.27 and higher. Show Sample Output


    0
    axi-cache search <searchterm>
    tarkasteve · 2010-07-05 00:16:03 3
  • Purge configuration files of removed packages on debian based systems

    Lists all packages in "rc" state and purge them one at a time.


    0
    dpkg -l | grep ^rc | cut -d' ' -f3 | xargs dpkg -P
    cyrusza · 2010-11-22 12:53:31 6
  • Save the debconf configuration of an installed package


    0
    debconf-copydb configdb copydb --pattern=<PACKAGE> --config="Name: copydb" --config="Driver: File" --config="Filename: ~/copydebconf.dat"
    ohe · 2011-08-29 14:00:42 3
  • Import a debconf configuration (from a copydebconf.dat file)


    0
    debconf-copydb copydb configdb --config="Name: copydb" --config ="Driver: File" --config="Filename: ~/copydebconf.dat"
    ohe · 2011-08-29 14:01:31 3
  • Remove all unused kernels with apt-get

    since awk was already there one can use it instead of the 2 greps. might not be faster, but fast enough


    0
    apt-get remove $(dpkg -l | awk "/^ii linux-(image|headers)/ && ! /`uname -r`/ {print \$2}")
    _john · 2011-10-09 13:58:47 4
  • Install 4 new package files

    after kernel build with make deb-pkg, I like to install the 4 newest packages that exist in the directory. Beware: might be fewer for you....


    0
    sudo dpkg -i `ls -tr *.deb | tail -n4`
    _john · 2011-10-09 14:20:11 3
  • Generate a list of installed packages on Debian-based systems

    This will print the name of every installed package on a Debian system.


    0
    aptitude search ~i -F %p
    dbbolton · 2011-10-15 00:31:10 8
  • Seach for packages on Debian using regex.

    # Search for an available package on Debian systems using a regex so it only matches packages starting with 'tin'.


    0
    aptitude search ^tin
    defiantredpill · 2011-10-20 17:51:36 3
  • Marks all manually installed deb packages as automatically installed.

    Marks all manually installed deb packages as automatically installed. Usefull to combine with apt-get install <all manually packages that we want> to have a clean installed debian-based system.


    0
    aptitude -F "%p" search \!~M~i~T | xargs apt-mark markauto
    gspadari · 2012-03-09 13:44:00 7
  • change default Web browser

    also use: update-alternatives --config gnome-www-browser


    0
    update-alternatives --config x-www-browser
    gwd · 2012-07-08 20:27:42 4
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Redirect incoming traffic to SSH, from a port of your choosing
Stuck behind a restrictive firewall at work, but really jonesing to putty home to your linux box for some colossal cave? Goodness knows I was...but the firewall at work blocked all outbound connections except for ports 80 and 443. (Those were wide open for outbound connections.) So now I putty over port 443 and have my linux box redirect it to port 22 (the SSH port) before it routes it internally. So, my specific command would be: $iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-ports 22 Note that I use -A to append this command to the end of the chain. You could replace that with -I to insert it at the beginning (or at a specific rulenum). My linux box is running slackware, with a kernel from circa 2001. Hopefully the mechanics of iptables haven't changed since then. The command is untested under any other distros or less outdated kernels. Of course, the command should be easy enough to adapt to whatever service on your linux box you're trying to reach by changing the numbers (and possibly changing tcp to udp, or whatever). Between putty and psftp, however, I'm good to go for hours of time-killing.

Send pop-up notifications on Gnome
The title is optional. Options: -t: expire time in milliseconds. -u: urgency (low, normal, critical). -i: icon path. On Debian-based systems you may need to install the 'libnotify-bin' package. Useful to advise when a wget download or a simulation ends. Example: $ wget URL ; notify-send "Done"

Block an IP address from connecting to a server
This appends (-A) a new rule to the INPUT chain, which specifies to drop all packets from a source (-s) IP address.

notify brightness level [custom]
Brightness indicator to be used in scripts that adjust brightness [especially sys that doesn't support automatically]

get all Amazon cloud (amazonws etc) ipv6 subnets

Convert epoch date to human readable date format in a log file.

Wait for file to stop changing
This loop will finish if a file hasn't changed in the last 10 seconds. . It checks the file's modification timestamp against the clock. If 10 seconds have elapsed without any change to the file, then the loop ends. . This script will give a false positive if there's a 10 second delay between updates, e.g. due to network congestion . How does it work? 'date +%s' gives the current time in seconds 'stat -c %Y' gives the file's last modification time in seconds '$(( ))' is bash's way of doing maths '[ X -lt 10 ]' tests the result is Less Than 10 otherwise sleep for 1 second and repeat . Note: Clever as this script is, inotify is smarter.

Adhoc tar backup
Creates a quick backup with tar to a remote host over ssh.

Kill all processes that listen to ports begin with 50 (50, 50x, 50xxx,...)
Run netstat as root (via sudo) to get the ID of the process listening on the desired socket. Use awk to 1) match the entry that is the listening socket, 2) matching the exact port (bounded by leading colon and end of column), 3) remove the trailing slash and process name from the last column, and finally 4) use the system(…) command to call kill to terminate the process. Two direct commands, netstat & awk, and one forked call to kill. This does kill the specific port instead of any port that starts with 50. I consider this to be safer.

see the TIME_WAIT and ESTABLISHED nums of the network
see the TIME_WAIT and ESTABLISHED nums of the network

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