adaptive_scope — define the scope applicable to adaptive delivery (AD)
adaptive_scope = "auto"
This directive is only valid if the Momentum adaptive module is loaded. See “adaptive – Adaptive Delivery”.
This option controls the scope of adaptive delivery, making it local to the node or cluster-wide (i.e., global). It can be be set to
auto. When it is set to
auto, the scope will be global if the binding is DuraVIP™ enabled and local for all other cases.
When it is set to
global for a binding::domain:
AD is cluster-wide for that binding::domain.
The stats will be aggregated across all MTA nodes. Although stats are replicated across the cluster, rules are only evaluated for the binding::domain pair on the node where messages have been sent. This may cause a small latency for a recently transferred virtual IP that has activity in its previous host (but only if the transfer occurs while rules are being evaluated).
Any action triggered for a binding::domain, where
adaptive_scopeis global, will affect the same binding::domain across all MTA nodes.
adaptive_scope evaluates to "global" for a binding::domain combination, it does not imply that it will also evaluate to the same value for that binding alone.
adaptive_scope evaluates to "global" for a binding scope, the age set for that binding through the warmup action will be applied to the binding across the whole cluster.
The following use cases apply to the
In a standalone MTA,
adaptive_scopeis local no matter what value the option is set to.
In a cluster where more than one MTA is doing the sending and all traffic goes through a network router, you will want to set
globalfor the relevant bindings/domains. This is because the outside world sees only one source IP.
When a binding is DuraVIP™ enabled, it may be relocated to another host. For this reason, set the scope to
auto(which is effectively
globalfor a DuraVIP™ binding).
In all other circumstances, set the scope to
localto save CPU and network bandwidth. For example, where different IPs are used for different bindings (and the binding is not DuraVIP™),
adaptive_scopeshould be local.
The default value for this option is
adaptive_scope is valid in the binding, binding_group, domain, and global scopes.