User-Defined Chains
User-defined chains provide a way to group rules logically. These chains are called from built-in chains as targets. At any point in the chain, you can call a user-defined chain from the same table. When a user-defined chain terminates with no matches, it returns to the next argument in the calling chain.
When creating user-defined chains, names should be lowercase because uppercase is reserved for built-in chains and targets. The name cannot be one of the built-in names or special values.
Get Special Edition Using Linux®, Sixth Edition now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
