Apply Hardened Security for Linux Services & Applications

1. When configuring services, what Linux directory typically contains server configuration files? /etc

2. What command disables remote access to the MySQL Database? Is this a security hardening best practice? Bind-address=YOUR-SERVER-IP, If you don’t need remote access, then binding should be considered a best practice.

3. What is a Linux runlevel for a specific service of application? What command allows you to define the runlevel uniquely for a service or application? 0 – System halt; no activity, the system can be safely powered down. 1 – Single user. 2 – Multiple users, no NFS (network filesystem). 3 – Multiple users, command line interface; the standard runlevel for most Linux-based server hardware. 4 – User-definable. 5 – Multiple users, GUI. 6 – Reboot. telinit

4. What is the Apache Web Server? Review the /etc/httpd/conf/httpd.conf configuration file, and point out a setting that could enhance security. Web server application noted in its help creating the World Wide Web, ResourceConfig /dev/null

5. OpenSSH is the de facto method to remotely access Linux systems. Explain why the use of telnet is discouraged. Associated messages including passwords are sent in cleat text so if a hacker is using a packet sniffer then he now has access to any usernames or passwords.

6. What are Symbolic links?

A special type of file that contains a reference to another file or directory in the form of an absolute or relative path

7. Why is it recommended to disable Symbolic Links in MySQL? To prevent various security risks

8. Why would you add the ‘skip-networking’ command?
To prevent remote access and to disallow access to load a local file.

9. What two files does sendmail create while processing a message? File: “df”: This stores the body of the message. File: “qf”: This stores the headers and other information. 10. What command can you use locally to find the sendmail’s version number? sendmail -d0.4 -bv root