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| Source daemon | Destination | Port | Protocol | Note |
|---|---|---|---|---|
| Arbiter | Synchronizer | 7765 | HTTPS | |
| Arbiter | Scheduler | 7768 | HTTPS | |
| Arbiter | Poller | 7771 | HTTPS | |
| Arbiter | Reactionner | 7769 | HTTPS | |
| Arbiter | Receiver | 7773 | HTTPS | |
| Arbiter | Arbiter | 7770 | HTTPS | Only if there is a arbiter slave, and only from the the master to theslave |
| Arbiter | Broker | 7772 | HTTPS |
The scheduler
Role
The scheduler daemon manages the dispatching of checks and actions to the poller and reactionner daemons respectively. The scheduler daemon is also responsible for processing the check result queue, analyzing the results, doing correlation and following up actions accordingly (if a service is down, ask for a host check). It does not launch checks or notifications. It just keeps a queue of pending checks and notifications for other daemons of the architecture (like pollers or reactionners). This permits distributing load equally across many pollers. There can be many schedulers for load-balancing or hot standby roles. Status persistence is achieved using a retention module.
Other daemon connexions
The scheduler daemon open the 7768 port. It will get from it the configuration from the Arbiter daemon at each configuration change.
It will also get on this port the jobs from the other daemons (poller, reactionner and broker). The other daemons are consuming action and data from the scheduler.
The scheduler connexions
In one specific case, the scehduler open connexions to another daemons. This case is when there is a passive poller. this case will be saw on the poller part.
Data
This daemon is hosting the whole configuration. It have access to the whole contact list, but only a part of the realm hosts.
Connexions summary
| Source | Destination | Port | Protocol | Note |
|---|---|---|---|---|
| Scheduler | Poller | 7771 | HTTPS | Only if there is a passive poller. |
The poller
The poller daemon launches check plugins as requested by schedulers. When the check is finished it returns the result to the schedulers. Pollers can be tagged for specialized checks (ex. Windows versus Unix, customer A versus customer B, DMZ). There can be many pollers for load-balancing or hot standby spare roles.
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