Parameter:
SERVER_AVAILABILITY_THRESHOLDShort description: Threshold for the availability index – below this value the server no longer accepts new client sessions (cluster failover).
Profile
Parameter | SERVER_AVAILABILITY_THRESHOLD |
Category | Performance / Memory |
Component | Server |
Available since | 10.0 |
Supported versions | 10.0, 11.0, 12.0, 14.0, 14.5, 14.5.1 |
GUI equivalent | Server document (Server Tasks → Cluster) |
Possible values | 0–100 (0 = always available, 100 = never; typically 20–70) |
Description
Domino continuously calculates an availability index (0–100) from response times and load. If the value falls below the threshold, the cluster manager directs new sessions to other cluster members – an elegant form of dynamic load balancing.
A value of 0 disables failover (the server always accepts), 100 effectively locks the server out permanently.
Example configuration
SERVER_AVAILABILITY_THRESHOLD=30
Notes & pitfalls
- Only effective in cluster setups (
Cluster_Probe_Min_Hours& co.).
- The current index is shown by
show serveras Availability Index.
- For clean maintenance windows, prefer
set config SERVER_RESTRICTED=2instead of briefly manipulating this value.
- Very low values can delay failover – watch monitoring.
- Takes effect immediately after
set config; no restart needed.