Commands tagged logging (15)

  • Don't spam root. Log your cronjob output to syslog

    This command will log the output of your simple cronjobs to syslog, and syslog will take it from there. Works great for monitoring scripts which only produce simple output. Advantages: * This can be used by regular users, without modifying system files like /etc/syslog.conf * Reduce cron spam to root@localhost (Please stop spaming the sysadmins) * Uses common tools like syslog (and logrotate) so that you don't need to maintain yet another krufty logfile. * Still ensures that the output is logged somewhere, for posterity. Perhaps it's stored the secure, central syslog server, for example. * Seems to work fine on Ubuntu, CentOS, FreeBSD & MacOSX Show Sample Output


    6
    */5 * * * * root /usr/local/nagios/sbin/nsca_check_disk 2>&1 |/usr/bin/logger -t nsca_check_disk
    StefanLasiewski · 2010-07-02 00:47:05 8
  • Debug SSH at the Maximum Verbosity Level

    When debugging an ssh connection either to optimize your settings ie compression, ciphers, or more commonly for debugging an issue connecting, this alias comes in real handy as it's not easy to remember the '-o LogLevel=DEBUG3' argument, which adds a boost of debugging info not available with -vvv alone. Especially useful are the FD info, and the setup negotiation to create a cleaner, faster connection. Show Sample Output


    4
    alias sshv='ssh -vvv -o LogLevel=DEBUG3'
    AskApache · 2010-10-30 11:23:52 5
  • View all new log messages in real time with color

    This will show all changes in all log files under /var/log/ that are regular files and don't end with `gz` nor with a number Show Sample Output


    4
    find /var/log -type f -iregex '.*[^\.][^0-9]+$' -not -iregex '.*gz$' 2> /dev/null | xargs tail -n0 -f | ccze -A
    rubo77 · 2014-07-29 17:11:17 5
  • Monitor a file with tail with timestamps added


    3
    tail -f file |xargs -IX printf "$(date -u)\t%s\n" X
    unefunge · 2010-11-25 11:23:13 6
  • Automatic ssh Session Logger

    A wrapper around ssh to automatically provide logging and session handling. This function runs ssh, which runs screen, which runs script. . The logs and the screen session are stored on the server. This means you can leave a session running and re-attach to it later, or from another machine. . . Requirements: * Log sessions on a remote server * Transparent - nothing extra to type * No installation - nothing to copy to the server beforehand . Features: * Function wrapper delegating to ssh - so nothing to remember - uses .ssh/config as expected - passes your command line option to ssh * Self-contained: no scripts to install on the server * Uses screen(1), so is: - detachable - re-attachable - shareable * Records session using script(1) * Configurable log file location, which may contain variables or whitespace L="$HOME" # local variable L="\$HOME" # server variable L="some space" . Limitations: * Log dir/file may not contain '~' (which would require eval on the server) . . The sessions are named by the local user connecting to the server. Therefore if you detach and re-run the same command you will reconnect to your original session. If you want to connect/share another's session simply run: USER=bob ssh root@server . The command above is stripped down to an absolute minimum. A fully expanded and annotated version is available as a Gist (git pastebin): https://gist.github.com/flatcap/3c42326abeb1197ee714 . If you want to add timing info to script, change the command to: ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "$@" "mkdir -p \"${L%/*}\";screen -xRRS $USER script --timing=\"$L-timing\" -f \"$L\"";} Show Sample Output


    3
    ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "$@" "mkdir -p \"${L%/*}\";screen -xRRS $USER script -f \"$L\"";}
    flatcap · 2015-10-14 13:14:29 11
  • Read Python logs with tracebacks in color


    1
    pygmentize -l pytb myapp.log | less -SR
    manuq · 2013-01-10 03:13:41 5
  • creating you're logging function for your script

    You could also pipe to logger.


    1
    logger -t MyProgramName "Whatever you're logging"
    pdxdoughnut · 2013-10-22 16:34:49 7
  • Realtime lines per second in a log file, with history

    This is similar to standard `pv`, but it retains the rate history instead of only showing the current rate. This is useful for spotting changes. To do this, -f is used to force pv to output, and stderr is redirected to stdout so that `tr` can swap the carriage returns for new lines. (doesn't work correctly is in zsh for some reason. Tail's output isn't redirected to /dev/null like it is in bash. anyone know why? ???????) Show Sample Output


    1
    tail -f access.log | pv -l -i10 -r -f 2>&1 >/dev/null | tr /\\r \ \\n
    varenc · 2020-04-19 02:07:40 97
  • Analyze Apache Web Log Statistics starting on DATE x

    GoAccess is an open source real-time Apache web log analyzer and interactive viewer that runs in a terminal in *nix systems. It provides fast and valuable HTTP statistics for system administrators that require a visual server report on the fly. http://goaccess.prosoftcorp.com/ Show Sample Output


    0
    sed -n '/05\/Dec\/2010/,$ p' access.log | goaccess -s -b
    allinurl · 2010-12-13 17:37:33 4
  • creating you're logging function for your script

    Put this logging function in you're script, when need it call it. command || logme "Error with command"


    0
    logme(){ echo "$(date +%d-%m-%Y-%H:%M) => $0 @ $1 returned error" >> persoscript.log }
    qcjn · 2013-10-22 15:55:01 7
  • Monitor a log file, filling up all available space in the terminal window and preventing line wrap

    This bash one-liner will let you watch the tail end of a log file in real time.


    0
    watch -n 4 "tail -n $(expr $(tput lines) - 4) /var/log/apache2/access.log | cut -c 1-$(tput cols)"
    atw527 · 2013-12-03 23:45:25 10
  • Powershell Ping Logs Host Up/Down Events

    IMPORTANT: You need Windows PowerShell to run this command - in your Windows Command Prompt, type powershell Uses sajb to start a PowerShell background job that pings an IP host every 10 seconds. Any changes in the host's Up/Down state is time-stamped and logged to a file. Date/time stamps are logged in two formats: Unix and human-readable. A while(1) loop repeats the test every 10 seconds by using the sleep command. See the Sample Output for more detail. I use this command to log Up/Down events of my Motorola SB6141 cable modem (192.168.100.1). To end the logging, close the PowerShell window or use the "exit" command. Show Sample Output


    0
    sajb {$ip="192.168.100.1";$old=0;while(1){$up=test-connection -quiet -count 1 $ip;if($up-ne$old){$s=(date -u %s).split('.')[0]+' '+(date -f s).replace('T',' ')+' '+$ip+' '+$(if($up){'Up'}else{'Down'});echo $s|out-file -a $home\ping.txt;$old=$up}sleep 10}}
    omap7777 · 2015-12-28 20:33:08 15
  • Prepend text to stdout of running job

    Run a job in the background and prefix it's output with some string. This is particularly useful if you are running inside a docker container in a startup script (sue me, I'll run two jobs in a docker container if I want to) and you can run something like: /usr/sbin/nginx 2>&1 | awk '{print "[NGINX] " $0}' & /opt/jws-3.1/tomcat8/bin/catalina.sh run 2>&1 | awk '{print "[TOMCAT] " $0}' & while true; do ; done it can also be combined with tee to create a file log as well as a stdout log, for example if the script above where a script called "/bin/start-container.sh" then you could run /bin/start-container.sh | tee /var/log/containerlogs Show Sample Output


    0
    nginx 2>&1 | awk '{print "[NGINX] " $0}' &
    hvindin · 2017-04-25 22:18:38 20
  • tail all logs opened by all java processes

    Tail all logs that are opened by all java processes. This is helpful when you are on a new environment and you do not know where the logs are located. Instead of java you can put any process name. This command does work only for Linux. The list of all log files opened by java process: sudo ls -l $(eval echo "/proc/{$(echo $(pgrep java)|sed 's/ /,/')}/fd/")|grep log|sed 's/[^/]* //g'


    -1
    sudo ls -l $(eval echo "/proc/{$(echo $(pgrep java)|sed 's/ /,/')}/fd/")|grep log|sed 's/[^/]* //g'|xargs -r tail -f
    vutcovici · 2010-07-30 18:20:00 4
  • Polls fos network port usage


    -4
    while sleep 1; do date; (netstat -a -n | grep 80) ; done
    hute37 · 2011-05-16 07:56:56 6

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rot13 simple substitution cipher via command line
E.g. Useful for hiding spoilers in reviews, etc.

Show total size of each subdirectory, broken down by KB,MB,GB,TB

Find Malware in the current and sub directories by MD5 hashes
Command makes use of the Malware Hash Registry (http://www.team-cymru.org/Services/MHR/). It parses the current directory and subdirectories and calculates the md5 hash of the files, then prints the name and sends the hash to the MHR for a lookup in their database. The 3rd value in the result is the detection percentage across a mix of AV packages.

List out classes in of all htmls in directory
Lists out all classes used in all *.html files in the currect directory. usefull for checking if you have left out any style definitions, or accidentally given a different name than you intended. ( I have an ugly habit of accidentally substituting camelCase instead of using under_scores: i would name soemthing counterBox instead of counter_box) WARNING: assumes you give classnames in between double quotes, and that you apply only one class per element.

Remount an already-mounted filesystem without unmounting it
Necessary for fsck for example. The remount functionality follows the standard way how the mount command works with options from fstab. It means the mount command doesn't read fstab (or mtab) only when a device and dir are fully specified. After this call all old mount options are replaced and arbitrary stuff from fstab is ignored, except the loop= option which is internally generated and maintained by the mount command. It does not change device or mount point.

Google dictionary of word definitions
$ wget -qO - "http://www.google.com/dictionary/json?callback=dict_api.callbacks.id100&q=steering+wheel&sl=en&tl=en&restrict=pr,de&client=te" this does the actual google dictionary query, returns a JSON string encapsulated in some fancy tag $ sed 's/dict_api\.callbacks.id100.//' here we remove the tag beginning $ sed 's/,200,null)//' and here the tag end There are also some special characters which could cause problems with some JSON parsers, so if you get some errors, this is probably the case (sed is your friend). I laso like to trim the "webDefinitions" part, because it (sometimes) contains misleading information. $ sed 's/\,\"webDefinitions.*//' (but remember to append a "}" at the end, because the JSON string will be invalid) The output also contains links to mp3 files with pronounciation. As of now, this is only usable in the English language. If you choose other than English, you will only get webDefinitions (which are crap).

Recursively find top 20 largest files (> 1MB) sort human readable format
Search for files and list the 20 largest. $ find . -type f gives us a list of file, recursively, starting from here (.) $ -print0 | xargs -0 du -h separate the names of files with NULL characters, so we're not confused by spaces then xargs run the du command to find their size (in human-readable form -- 64M not 64123456) $ | sort -hr use sort to arrange the list in size order. sort -h knows that 1M is bigger than 9K $ | head -20 finally only select the top twenty out of the list

Check which modules your PHP is using

tar the current directory wihtout the absolute path
tars the current directory (and its children) in an archive of the same name (plus ".tar" :)) in the parent directory without the absolute path, so that when the archive is extracted, only the current directory name is created for the path. Assumes bash/zsh.

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