Firewall

Please note! This wiki is no longer maintained. Our documentation has moved to https://securityonion.net/docs/. Please update your bookmarks. You can find the latest version of this page at: https://securityonion.net/docs/Firewall.

Setup defaults to only allowing port 22 (ssh)

As of securityonion-setup - 20120912-0ubuntu0securityonion201, Setup now defaults to locking down the local ufw firewall to only allowing port 22 (ssh):
http://blog.securityonion.net/2016/03/securityonion-setup-20120912.html

There is a note at the end of Setup that tells you this and lets you know that, if you need to allow connections on other ports, you can run the new so-allow utility.

Sensors automatically add their own firewall rules to the master server

When you run Setup on a sensor-only installation, it will ssh to the master server and add new firewall rules to the master server to allow the sensor to connect on the following ports:

• 22/tcp (ssh)
• 4505/tcp (salt)
• 4506/tcp (salt)
• 7736/tcp (sguil)

so-allow

If you need to open ports for OSSEC agents, syslog devices, or analyst VMs, you can run so-allow and it will walk you through this process. so-allow also provides an option to add firewall rules for sensors although you shouldn't need this under normal circumstances since they should automatically add their own rules as described above.

This program allows you to add a firewall rule to allow connections from a new IP address.

What kind of device do you want to allow?

[a] - analyst - ports 22/tcp, 443/tcp, and 7734/tcp
[b] - Logstash Beat - port 5044/tcp
[c] - apt-cacher-ng client - port 3142/tcp
[f] - Logstash Forwarder - Standard - port 6050/tcp
[j] - Logstash Forwarder - JSON - port 6051/tcp
[l] - syslog device - port 514
[o] - ossec agent - port 1514/udp
[s] - Security Onion sensor - 22/tcp, 4505/tcp, 4506/tcp, and 7736/tcp

If you need to add any ports other than those listed above,
you can do so using the standard 'ufw' utility.

For more information, please see the Firewall page on our Wiki:
https://github.com/Security-Onion-Solutions/security-onion/wiki/Firewall

Please enter your selection (a - analyst, c - apt-cacher-ng client, l - syslog, o - ossec, or s - Security Onion sensor, etc.):

To view existing rules granted through the use of so-allow, use the following command:

so-allow-view

If you have upgraded from Security Onion 12.04 and you receive duplicate profile warnings for UFW when adding rules, please see:
https://github.com/Security-Onion-Solutions/security-onion/wiki/Upgrading-from-12.04-to-14.04#clean-up

More ufw documentation

For more information about manually adding ufw firewall rules or if you're still running a version of Setup older than securityonion-setup - 20120912-0ubuntu0securityonion201, then you can reference the original firewall documentation.