This is for my Intro to Linux Class. We use BASH and Vi Editor. Thank you for yo

Question

This is for my Intro to Linux Class. We use BASH and Vi Editor. Thank you for your help in advance.

STAGE 2 | Setting A Cronjob With Crontab

For this part of the lab we will create another script and add in a cron job.

Write a script called ‘log_copy’. This script should be run every hour via a cron job. It’s input will be the log file from the previous bash script. One way to do this is to “grep” the information from the log file that matches a timestamp equal to the last hour. Use the following hints to construct this BASH script.

1. Determine what the last hour is and save it as a variable as shown below (check date man page)

LAST_HOUR=”$(( $(date +%l) - 1 ))”

if LAST_HOUR is less than 10 then pad a 0 in front i.e. : 6 should become 06

2. Create the search string and save it as a variable as shown below

SEARCH_STRING=$(date +“%b-%d-%Y-${LAST_HOUR}:”)

The above string will search through your ‘Server_Info.log’ file for timestamps matching the last hour.

3. Search the log file with the following command inside of your ‘log_copy’ script.

grep “${SEARCH_STRING}”

4.                   Output the results to a new log file. Name this new log file ‘Server_Hourly.log’. Make sure that this new log file is located inside of your ‘logs’ directory and that the script ‘log_copy’ is located inside of your home directory.

5.                   Once both scripts are created test them out by running the ‘IsTheServerUp.bash’ script first (run it 5-6 times). Make sure a log file called ‘Server_Info.log’ was saved inside of your ‘logs’ directory after running this script. Once you see that a log file was created and is populated with the result of the script you can then run your ‘log_copy’ script (before running ‘log_copy’ script, open ‘Server_Info.log’ file and change the hour of the first two lines to one hour before). After running your second script, make sure that a second log file called ‘Server_Hourly.log’ was created within your ‘logs’ directory and that it is populated with the results of the second script.

6.                   After verifying that both scripts work you will need to create 2 cron jobs so that these scripts are ran automagically. Create a new cron job by running the following command:

% crontab -e

NOTE: If it prompts you to select an editor, select the first editor (Option 1 - /usr/bin/vim/basic) Add the following rules to your crontab:

•   Run your ‘IsTheServerUp.bash’ script every 10 minutes.

•   Run your ‘log_copy’ script every hour.

•   Make sure you add the entire path to your script so /home/users#/your_username/script

•   Replace # with your user group #. HINT: use the pwd command

Explanation / Answer

Well, it seems few information is missing but lemme paste the scripts:

log_copy.bash

#!/bin/bash

LAST_HOUR=$(( $(date +%l) - 1 ))

SEARCH_STRING=$(date +"%b-%d-%Y-${LAST_HOUR}:")

grep "${SEARCH_STRING}" > "/home/users/vijay/log/Server_Hourly.log"

------------------------------------------------------------------------------------------

Now, create one file named scheduler with below mentioned content:

scheduler

#!/bin/bash
PATH=/bin;/usr/local/bin;/usr/bin;/usr/sbin;/sbin;
*/10 * * * * bash /home/users/vijay/your_username/script/IsTheServerUp.bash
0 * * * * bash /home/users/vijay/your_username/script/log_copy.bash

---------------------------------------------------------------------------------------------------------

Now, execute below menioned command to schedule the jobs. It will directly schedule the job without any need for an editor:

sudo crontab /path-to-scheduler/scheduler

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