Commands by UnixNeko (4)

  • Check if a machine is online

    PING parameters c 1 limits to 1 pinging attempt q makes the command quiet (or silent mode) /dev/null 2>&1 is to remove the display && echo ONLINE is executed if previous command is successful (return value 0) || echo OFFLINE is executed otherwise (return value of 1 if unreachable or 2 if you're offline yourself). I personally use this command as an alias with a predefined machine name but there are at least 2 improvements that may be done. Asking for the machine name or IP Escaping the output so that it displays ONLINE in green and OFFLINE in red (for instance).


    9
    ping -c 1 -q MACHINE_IP_OR_NAME >/dev/null 2>&1 && echo ONLINE || echo OFFLINE
    UnixNeko · 2012-02-09 06:30:55 7
  • Extract a .gz file with privilege

    Extracting .gz files and placing the output in another directory in one command line is convenient thing. I just followed some how-to to install Nagios on Ubuntu Lucid Lynx but they give the method to install from archives. I wished to install from the repository. If you do so some files are missing. I've not tested yet but this is an example command line I did to extract sudo sh -c 'gunzip -c /usr/share/doc/nagios3-common/examples/template-object/templates.cfg.gz > /etc/nagios3/objects/templates.cfg' We need privilege to write the destination file. Show Sample Output


    0
    sudo sh -c 'gunzip -c source.gz > destination'
    UnixNeko · 2011-07-05 23:51:01 1
  • Rip CD

    Can be useful to rip a CD. Show Sample Output


    -1
    ripit -c 0 --outputdir $1 --nosubmission
    UnixNeko · 2011-06-12 12:29:26 0
  • Reload gnome-panel

    I have some problems with gnome panel which does not load completely leaving me without the actual GUI. This commands helps to kill the gnome-panel process then it should be relaunch automatically.


    -2
    pgrep -lf gnome-panel | awk '{if ($2=="gnome-panel") print $1}' | xargs kill -9
    UnixNeko · 2011-06-12 12:23:27 2

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Does a traceroute. Lookup and display the network or AS names and AS numbers.
From the man page. lft ? display the route packets take to a network host/socket using one of several layer-4 protocols and methods; optionally show heuristic network information in transitu -A Enable lookup and display of of AS (autonomous system) numbers (e.g., [1]). This option queries one of several whois servers (see options 'C' and 'r') in order to ascertain the origin ASN of the IP address in question. By default, LFT uses the pWhoIs service whose ASN data tends to be more accurate and more timely than using the RADB as it is derived from the Internet's global routing table. -N Enable lookup and display of network or AS names (e.g., [GNTY-NETBLK-4]). This option queries Prefix WhoIs, RIPE NCC, or the RADB (as requested). In the case of Prefix WhoIs or RADB, the network name is displayed. In the case of RIPE NCC, the AS name is displayed.

Find the package that installed a command

Set OS X X11 to use installed Mathematica fonts

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Prints any IP out of a file

Archive all files that have not been modified in the last days
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