Commands tagged log (39)

  • This will log your internet download speed. You can run gnuplot -persist <(echo "plot 'bps' with lines") to get a graph of it.


    9
    echo $(date +%s) > start-time; URL=http://www.google.com; while true; do echo $(curl -L --w %{speed_download} -o/dev/null -s $URL) >> bps; sleep 10; done &
    matthewbauer · 2009-09-19 21:26:06 0
  • Using the grep command, retrieve all lines from any log files in /var/log/ that have one of the problem states


    6
    grep -2 -iIr "err\|warn\|fail\|crit" /var/log/*
    miketheman · 2009-06-17 19:41:04 2
  • Uses date to grep de logfile for today and uses it to get the last hour logs. Can be used to get last minute logs or today's logs. Show Sample Output


    6
    grep -i "$(date +%b\ %d\ %H)" syslog
    rubenmoran · 2010-05-23 16:18:15 4
  • Returns logs between HH:M[Mx-My], for example, between 13:40 and 13:45. Show Sample Output


    6
    grep -i "$(date +%b" "%d )13:4[0-5]" syslog
    rubenmoran · 2010-05-23 16:30:46 3
  • with discard wilcards in bash you can "tail" newer logs files to see what happen, any error, info, warn... Show Sample Output


    5
    tail -f *[!.1][!.gz]
    piscue · 2009-03-06 16:24:44 3
  • This command finds the 5 (-n5) most frequently updated logs in /var/log, and then does a multifile tail follow of those log files. Alternately, you can do this to follow a specific list of log files: sudo tail -n0 -f /var/log/{messages,secure,cron,cups/error_log} Show Sample Output


    5
    ls -drt /var/log/* | tail -n5 | xargs sudo tail -n0 -f
    kanaka · 2009-07-22 14:44:41 0
  • just change the date following the -r flag, and/or the user name in the user== conditional statement, and substitute yms_web with the name of your module


    4
    svn log -v -r{2009-05-21}:HEAD | awk '/^r[0-9]+ / {user=$3} /yms_web/ {if (user=="george") {print $2}}' | sort | uniq
    jemptymethod · 2009-06-05 14:07:28 3

  • 4
    zcat access_log.*.gz | awk '{print $7}' | sort | uniq -c | sort -n | tail -n 20
    tkb · 2009-12-11 09:36:30 0
  • 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 0

  • 4
    curl http://whatthecommit.com/index.txt
    nickoe · 2011-12-29 22:35:28 0
  • This one is tried and tested for Ubuntu 12.04. Works great for tailing any file over http.


    4
    (echo -e "HTTP/1.1 200 Ok\n\r"; tail -f /var/log/syslog) | nc -l 1234
    adimania · 2013-02-09 06:15:42 0
  • This truncates any lines longer than 80 characters. Also useful for looking at different parts of the line, e.g. cut -b 50-100 shows columns 50 through 100.


    3
    tail -f logfile.log | cut -b 1-80
    plasticboy · 2009-03-26 18:41:57 1

  • 3
    tail -f /var/log/squid/access.log | perl -p -e 's/^([0-9]*)/"[".localtime($1)."]"/e'
    godzillante · 2011-07-06 08:55:27 3
  • When you have one of those (log)files that only has epoch for time (since no one will ever look at them as a date) this is a way to get the human readable date/time and do further inspection. Mostly perl-fu :-/


    2
    perl -F' ' -MDate::Format -pale 'substr($_, index($_, $F[1]), length($F[1]), time2str("%C", $F[1]))' file.log
    coffeeaddict_nl · 2009-08-13 13:57:33 0
  • This logs the titles of the active windows, thus you can monitor what you have done during which times. (it is not hard to also log the executable name, but then it is gets too long) Show Sample Output


    2
    while true; do (echo -n $(date +"%F %T"):\ ; xwininfo -id $(xprop -root|grep "ACTIVE_WINDOW("|cut -d\ -f 5) | grep "Window id" | cut -d\" -f 2 ) >> logfile; sleep 60; done
    BeniBela · 2015-09-23 23:00:14 13
  • Really useful way to combine less and grep while browsing log files. I can't figure out how to make it into a true oneliner so paste it into a script file called lgrep: Usage: lgrep searchfor file1 [file2 file3] Advanced example (grep for an Exception in logfiles that starts with qc): lgrep Exception $(find . -name "qc*.log") Show Sample Output


    1
    argv=("[email protected]"); rest=${argv[@]:1}; less -JMN +"/$1" `grep -l $1 $rest`
    lassel · 2009-10-16 17:36:16 0
  • This command will return a full list of Error 404 pages in the given access log. The following variables have been given to awk Hostname ($2), ERROR Code ($9), Missing Item ($7), Referrer ($11) You can then send this into a file (>> /path/to/file), which you can open with OpenOffice as a CSV


    1
    sudo awk '($9 ~ /404/)' /var/log/httpd/www.domain-access_log | awk '{print $2,$9,$7,$11}' | sort | uniq -c
    ninjasys · 2010-04-09 10:31:50 3

  • 1
    git log -p -z | perl -ln0e 'print if /[+-].*searchedstring/'
    takeshin · 2010-06-13 07:41:22 0
  • 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


    1
    goaccess -f /var/log/apache2/access.log -s -b
    allinurl · 2010-10-25 20:03:18 1
  • * Replace USERNAME with the desired svn username * Replace the first YYYY-MM-DD with the date you want to get the log (this starts at the midnight event that starts this date) * Replace the second YYYY-MM-DD with the date after you want to get the log (this will end the log scan on midnight of the previous day) Example, if I want the log for December 10, 2010, I would put {2010-12-10}:{2010-12-11} Show Sample Output


    1
    svn log -r '{YYYY-MM-DD}:{YYYY-MM-DD}' | sed -n '1p; 2,/^-/d; /USERNAME/,/^-/p' | grep -E -v '^(r[0-9]|---|$)' | sed 's/^/* /g'
    antic · 2010-12-22 17:52:19 1
  • This awk command prints a histogram of the number of times 'emergency' is the first word in a line, per day, in an irssi (IRC client) log file. Show Sample Output


    0
    awk '/^--- Day changed (.*)/ {st=""; for (i=0;i<ar[date];i++) {st=st"*"} print date" "st; date=$7"-"$5"-"$6} /> emergency/ {ar[date]++} END {st=""; for (i=0;i<ar[date];i++) {st=st"*"}; print date" "st}' #engineyard.log
    menicosia · 2010-02-24 22:54:34 1
  • 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 0
  • The same with colors


    0
    tail -f /var/log/squid/access.loc | ccze -CA
    longdrink · 2011-07-15 14:58:53 2
  • If you don't have html2text Show Sample Output


    0
    curl -s 'http://whatthecommit.com/' | grep '<p>' | cut -c4-
    hputman · 2011-11-04 14:37:36 0
  • svn log -v --> takes log of all Filter1 -------- -r {from}{to} --> gives from and to revision Filter2 -------- awk of line 'r'with numbers Assign user=3rd column [ie; username] Filter3 -------- if username = George print details Filter4 -------- Print lines starts with M/U/G/C/A/D [* A Added * D Deleted * U Updated * G Merged * C Conflicted] Filter5 -------- sort all files Filter6 ------- Print only uniq file's name alone. Show Sample Output


    0
    svn log -v -r{2009-11-1}:HEAD | awk '/^r[0-9]+ / {user=$3} /./{if (user=="george") {print}}' | grep -E "^ M|^ G|^ A|^ D|^ C|^ U" | awk '{print $2}' | sort | uniq
    smilyface · 2011-12-05 07:36:44 0
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Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

list block devices
Shows all block devices in a tree with descruptions of what they are.

peak amount of memory occupied by any process with "FOO" in its name
Show the maximum amount of memory that was needed by a process at any time. My use case: Having a long-running computation job on $BIG_COMPUTER and judging whether it will also run on $SMALL_COMPUTER.   http://man7.org/linux/man-pages/man5/proc.5.html VmHWM: Peak resident set size ("high water mark")

Edit the list of to ignore files in the active directory
Standard command, but I always have to search for it... ;-)

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Email yourself a quick message
Usage: mailme message This is a useful function if you want to get notified about process completion or failure. e.g. $ mailme "process X completed"

Rename files in batch

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Filter the output of a file continously using tail and grep
The OPs solution will work, however on some systems (bsd), grep will not filter the data, unless the --line-buffered option is enabled.

Find the package that installed a command


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