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Commands tagged log from sorted by
Terminal - Commands tagged log - 39 results
grep -i "$(date +%b" "%d )13:4[0-5]" syslog
2010-05-23 16:30:46
User: rubenmoran
Functions: grep
Tags: log minutes

Returns logs between HH:M[Mx-My], for example, between 13:40 and 13:45.

grep -i "$(date +%b\ %d\ %H)" syslog
2010-05-23 16:18:15
User: rubenmoran
Functions: grep
Tags: log date

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.

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

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

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
2010-02-24 23:10:03
User: MarcoN
Functions: awk

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.

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
2010-02-24 22:54:34
User: menicosia
Functions: awk

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.

zcat access_log.*.gz | awk '{print $7}' | sort | uniq -c | sort -n | tail -n 20
argv=("$@"); rest=${argv[@]:1}; less -JMN +"/$1" `grep -l $1 $rest`
2009-10-16 17:36:16
User: lassel
Functions: less
Tags: bash less log grep

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:


lgrep searchfor file1 [file2 file3]

Advanced example (grep for an Exception in logfiles that starts with qc):

lgrep Exception $(find . -name "qc*.log")

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 &
2009-09-19 21:26:06
User: matthewbauer
Functions: date echo sleep

This will log your internet download speed.

You can run

gnuplot -persist <(echo "plot 'bps' with lines")

to get a graph of it.

perl -F' ' -MDate::Format -pale 'substr($_, index($_, $F[1]), length($F[1]), time2str("%C", $F[1]))' file.log
2009-08-13 13:57:33
Functions: perl
Tags: perl log

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 :-/

ls -drt /var/log/* | tail -n5 | xargs sudo tail -n0 -f
2009-07-22 14:44:41
User: kanaka
Functions: ls sudo tail xargs
Tags: bash tail log watch

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}

grep -2 -iIr "err\|warn\|fail\|crit" /var/log/*
2009-06-17 19:41:04
User: miketheman
Functions: grep

Using the grep command, retrieve all lines from any log files in /var/log/ that have one of the problem states

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

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

tail -f logfile.log | cut -b 1-80
2009-03-26 18:41:57
User: plasticboy
Functions: cut tail
Tags: tail log

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.

tail -f *[!.1][!.gz]
2009-03-06 16:24:44
User: piscue
Functions: tail

with discard wilcards in bash you can "tail" newer logs files to see what happen, any error, info, warn...