Extract data from log file in specified range of time [duplicate] - bash

Question

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Filter log file entries based on date range
(5 answers)
Closed 6 years ago.
I want to extract information from a log file using a shell script (bash) based on time range. A line in the log file looks like this:
172.16.0.3 - - [31/Mar/2002:19:30:41 +0200] "GET / HTTP/1.1" 200 123 "" "Mozilla/5.0 (compatible; Konqueror/2.2.2-2; Linux)"
i want to extract data specific intervals. For example I need to look only at the events which happened during the last X minutes or X days ago from the last recorded data. I'm new in shell scripting but i have tried to use grep command.

Answer 1

You can use sed for this. For example:
$ sed -n '/Feb 23 13:55/,/Feb 23 14:00/p' /var/log/mail.log
Feb 23 13:55:01 messagerie postfix/smtpd[20964]: connect from localhost[127.0.0.1]
Feb 23 13:55:01 messagerie postfix/smtpd[20964]: lost connection after CONNECT from localhost[127.0.0.1]
Feb 23 13:55:01 messagerie postfix/smtpd[20964]: disconnect from localhost[127.0.0.1]
Feb 23 13:55:01 messagerie pop3d: Connection, ip=[::ffff:127.0.0.1]
...
How it works
The -n switch tells sed to not output each line of the file it reads (default behaviour).
The last p after the regular expressions tells it to print lines that match the preceding expression.
The expression '/pattern1/,/pattern2/' will print everything that is between first pattern and second pattern. In this case it will print every line it finds between the string Feb 23 13:55 and the string Feb 23 14:00.
More info here

Answer 2

Use grep and regular expressions, for example if you want 4 minutes interval of logs:
grep "31/Mar/2002:19:3[1-5]" logfile
will return all logs lines between 19:31 and 19:35 on 31/Mar/2002.
Supposing you need the last 5 days starting from today 27/Sep/2011 you may use the following:
grep "2[3-7]/Sep/2011" logfile

Answer 3

well, I have spent some time on your date format.....
however, finally i worked it out..
let's take an example file (named logFile), i made it a bit short.
say, you want to get last 5 mins' log in this file:
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:20:41 +0200] "GET
### lines below are what you want (5 mins till the last record)
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:27:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:30:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:30:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:30:41 +0200] "GET
172.16.0.3 - - [31/Mar/2002:19:30:41 +0200] "GET
here is the solution:
# this variable you could customize, important is convert to seconds.
# e.g 5days=$((5*24*3600))
x=$((5*60)) #here we take 5 mins as example
# this line get the timestamp in seconds of last line of your logfile
last=$(tail -n1 logFile|awk -F'[][]' '{ gsub(/\//," ",$2); sub(/:/," ",$2); "date +%s -d \""$2"\""|getline d; print d;}' )
#this awk will give you lines you needs:
awk -F'[][]' -v last=$last -v x=$x '{ gsub(/\//," ",$2); sub(/:/," ",$2); "date +%s -d \""$2"\""|getline d; if (last-d<=x)print $0 }' logFile
output:
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:27:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:30:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:30:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:30:41 +0200 "GET
172.16.0.3 - - 31 Mar 2002 19:30:41 +0200 "GET
EDIT
you may notice that in the output the [ and ] are disappeared. If you do want them back, you can change the last awk line print $0 -> print $1 "[" $2 "]" $3

Answer 4

I used this command to find last 5 minutes logs for particular event "DHCPACK", try below:
$ grep "DHCPACK" /var/log/messages | grep "$(date +%h\ %d) [$(date --date='5 min ago' %H)-$(date +%H)]:*:*"

Answer 5

You can use this for getting current and log times:
#!/bin/bash
log="log_file_name"
while read line
do
current_hours=`date | awk 'BEGIN{FS="[ :]+"}; {print $4}'`
current_minutes=`date | awk 'BEGIN{FS="[ :]+"}; {print $5}'`
current_seconds=`date | awk 'BEGIN{FS="[ :]+"}; {print $6}'`
log_file_hours=`echo $line | awk 'BEGIN{FS="[ [/:]+"}; {print $7}'`
log_file_minutes=`echo $line | awk 'BEGIN{FS="[ [/:]+"}; {print $8}'`
log_file_seconds=`echo $line | awk 'BEGIN{FS="[ [/:]+"}; {print $9}'`
done < $log
And compare log_file_* and current_* variables.