Each new host will impact the license count.
You have multiple options:
1. Instead of monitoring each individual server, use the cluster virtual IP (VIP) to monitor them, this would then always point to the active node.
2. Setup each individual host and monitor them and use BPI or check_cluster.
3. You could also just add multiple services to a host that check different servers (say a dummy host like BPI uses or your VIP host).
Here's an example of check_cluster:
1. Make sure that you are monitoring the services (PING in this example) on all servers (you can disable notifications for them, this is important so you don't notifications when they are down), these service checks are what will be used by the check_cluster plugin and need to exist.
2. Create a new command:
- Command Name: check_service_cluster
- Command Line: $USER1$/check_cluster --service -l $ARG1$ -w $ARG2$ -c $ARG3$ -d '$ARG4$'
- Command Type: check command
3. Create the service cluster check:
- Description: PING_Cluster
- Check command: check_service_cluster
- $ARG1$: PING_Cluster
- $ARG2$: 4 <- Set this to one MORE than your total number of services (3 services + 1 = 4) - We don't care about warnings in this example
- $ARG3$: 2 <- Set this to one LESS than your total number of services (3 services - 1 = 2)
- $ARG4$: $SERVICESTATEID:yourhost1:PING$,$SERVICESTATEID:yourhost2:PING$,$SERVICESTATEID:yourhost3:PING$
NOTE: The hostname and the service description in $ARG4$ need to be exact (case sensitive).
The way this would work is that whenever that service is not running on ANY of the nodes it would generate a CRITICAL. So the check_cluster uses the statuses of all of each individual service checks to determine if there is an issue and since you disabled the notifications on the individual services you won't get those notifications, this is the service that will do the notifying.
Please read here for more information:
https://assets.nagios.com/downloads/nag ... sters.html