Exercise 5 on lab 8 done

Labb8/ovning5/README.md

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+# failed\_logins.sh #
+This is a small Bash script I wrote for a programming & scripting course at
+school. The script checks for failed SSH logins in /var/log/auth.log by default.
+The failed logins are then sent by e-mail to the admin user specified in the
+Admin variable.
+The script only mails new failed login attempts since it was last run to avoid 
+cluttering the admin's mailbox.
+
+## Usage ##
+The script is meant to run from a cronjob, for example once every hour or day
+or whatever suits your needs. An example (15 minutes after every hour) would be:
+```
+15 * * * * /home/admin/failed_logins.sh
+```
+
+## Compability ##
+So far I've only tested it on Ubuntu 13.04. The binaries used in the script are
+hardcoded to avoid unsane environments. The path to these hardcoded binaries
+could change on other Linux dists and other *NIX.
+
+The script uses sed, awk (standrad awk), egrep, cat, printf, mail, rm, tail,
+mktemp and regular grep. All of these utilities are pretty standard on a 
+Debian/Ubuntu machine, except for mail which is not included in for example 
+Ubuntu Desktop. On both Ubuntu and Debian this can be installed with 
+`sudo apt-get install mailutils`.
+
+