Security Groups are reusable collections of firewall rules, which can be attached to any of your servers. They're commonly used to hold related rules that perform a certain task. For example:
While you're logged into the Control Panel , click Networking on the left menu. Then go to the Security Group module. From there, click Add Group on the top right of the screen.
You'll need to give your group a label, to help you identify it throughout the rest of the Control Panel. You can always change this label later if you need to.
Once your group has been created, you can start modifying the firewall rules within it. If you've ever used tools like
iptables
, the interface may feel familiar to you.
The form for modifying Security Groups has two separate sections that specify the direction of traffic, one for Inbound traffic and one for Outbound. It's important to make sure that the rules you create go in the correct section.
A Source IP is the address that a network packet was sent from. A Dest. IP is the address that a packet is intended to be sent to. The same logic applies for source/destination ports.
Please note that if you do not specify a protocol, port, or IP address as part of a rule, that rule will apply to all traffic.
Firewall rules within a Security Group are always applied to traffic in order, from top to bottom.
Putting a DROP
or REJECT
rule in the middle of your group, will effectively stop any rules below it
from being applied. If that isn't what you need, it's important to specify a protocol, port or IP, so that any "other"
traffic can continue onto the following rules.
Since order matters, you may find you need to move an existing rule to a higher or lower position within a group. If this happens, you can hover your mouse over the relevant rule, and drag it to another position with the 6 dots on the left (seen circled in red below).
Once you've finished configuring your Security Group, you can read about how to apply it one of your servers using the article here.
Once you've attached a Security Group to any servers, any future updates you make to the group will be reflected on those servers automatically.
Security Groups cannot be deleted if they are currently in use by any servers. Please note that once a Security Group has been deleted, it cannot be recovered.