types of files that bad guys leave behind for their return.Finally, keep your disaster recovery plan somewhere safe; saving it as a file
on the machine in question is a very bad move.
References
https://help.ubuntu.com/community/InstallingSecurityTools
—Ubuntu community documentation of and suggestions for various
security tools
https://nmap.org—The official site for Nmap
http://www.tripwire.org—Information and download links for the open source
version of Tripwire
http://www.ubuntu.com/usn—The official Ubuntu security notices list, which
is well worth watching
https://help.ubuntu.com/community/UFW—Ubuntu community
documentation for UFW
https://wiki.ubuntu.com/UncomplicatedFirewall—Ubuntu
documentation for UFW
https://gitlab.com/apparmor/apparmor/wikis/home/—The official
documentation for AppArmor
https://help.ubuntu.com/community/AppArmor—Ubuntu community
documentation for AppArmor
https://wiki.ubuntu.com/Security/Features—An Ubuntu wiki page that
outlines and describes security features, Ubuntu, and configuration