The firewall rules are managed by iptables, a command that seems scary and arcane, but makes sense when you know how it works. Learn to use iptables in this video.
- [Instructor] Iptables is a software package…that acts as a firewall.…Rules for the Iptables firewall software…can seem complex and difficult to understand.…These rules are put together in arrangements called chains,…and using these, packets are evaluated…against rules one at a time.…If a rule or condition matches the packet,…whatever action is specified by that rule is taken.…If a packet doesn't match,…the next rule is evaluated against it, and so on,…until there's a match,…or until the end of the chain is reached.…
Chains have a default action to take if a packet…gets all the way through without matching anything.…Chains can refer to other chains,…making it fairly easy to set up conditional flows.…There are chains for input,…or for information coming into the system.…For forward, in the case where the system is doing that,…and routing for systems behind it.…And output, for packets flowing from the system…out to another network.…There are also a few predefined actions that we can use…either in rules, or as default actions.…
- Name the tool that is often used to find out what ports are open on a remote server.
- Explain what a firewall will do without any additional configuration.
- Identify what you append a rule to in iptables.
- Explain what needs to be added to a site to allow the use of HTTPS.
- List the two components of a keypair.