Snort 2 to Snort 3 migration

Let’s say you have an IDS or IPS system using Snort 2. You also have a working Snort 2 configuration and a set of rules that you have built over a considerable period of time. Now, you wish to migrate to Snort 3. There are a few challenges. Firstly, Snort 3 syntax has changed and is not backward compatible with Snort 2. Secondly, Snort 3 uses a Lua-based configuration, and we cannot use the existing Snort 2 configuration as is. In this section, let’s discuss the topic of migrating from Snort 2 to Snort 3.

Migrating the rules

Snort 3 extends the detection and signature matching capabilities of the Snort IDS/IPS platform. Along with this, some of the syntax rules have also changed and it does not provide backward compatibility to the Snort 2 equivalent. To use any Snort 2 signatures with Snort 3, they need to be converted to their Snort 3 versions.

Although the Snort team recommends rewriting the signatures manually, taking into account...