In Unbound, forward-zones (or stub-zones) are stored as leaf elements of the unified red-black tree to maintain delegations for DNS tree.
Theoretically, setting up thousands of forward-zones can be considered the same situation that Unbound caches _only_ thousands of delegation information and performance is unlikely to degrade, but performance may vary depending on usage, so you may want to do some performance testing. A.Schulze via Unbound-users <unbound-users@lists.nlnetlabs.nl>: > Hello, > > over the last years I run unbound with zero or a small number of > configures forward-zones. > Now, I was asked to configure 1-2 thousand forward-zones. Do I have to be > concerned about performance degration? >
