Traditional behaviour was to regard all dependecies as cumulative (e.g., the parent considered unreachable if any one dependency is violated), commit ed58922389 made all dependencies regarded redundant (e.g., the parent considered unreachable only if all dependency are violated). This may lead to unrelated services (or even hosts vs. services) inadvertantly regarded to be redundant to each other.
Most importantly, applying the explicit "disable-host-service-checks" dependency described in the "Monitoring Basics" chapter will defeat all other dependencies.
This commit introduces a new "redundancy_group" attribute for dependencies.
Specifying a redundancy_group causes a dependency to be regarded as redundant only inside that redundancy group.
Dependencies lacking a redundancy_group attribute are regarded as essential for the parent.
This allows for both cumulative and redundant dependencies and even a combination (cumulation of redundancies, like SSH depeding on both LDAP and DNS to function, while operating redundant LDAP servers as well as redundant DNS resolvers).
This commit lacks changes to the tests.
cfef9fdadc