Your monitor and recipient settings define when alerts are sent, and who receives alerts.
The monitor is disabled.
Alerting is disabled in the monitor settings (the Enable alerts? option).
A blackout period is active for the monitor.
A blackout period is active for the recipient.
If a monitor is included in a recipient group, it sends alerts only to recipients from that group. Other recipients will not get alerts from this monitor.
The monitor uses the Round Robin monitoring mode, and an error is detected at only one location. Round Robin monitors trigger alerts only when two or more locations fail during the same interval.
The monitor uses the SLA (MultiPOP) monitoring mode, and the number of locations in the error is less than your configured limit (the SLA Alerts option in your AlertSite preferences).
The recipient’s contact details (email address, phone number, and so on) are incomplete or incorrect. Double-check the spelling, make sure phone numbers are specified with area code and country code (1 for US and Canada). See examples in Creating a Recipient.
You configured recipient groups to trigger alerts only for specific error types, and the monitor failed with an error that is not handled by any recipient group for that monitor (see Alert Routing by Error Type).
The recipient has availability alerts turned off (see Recipient Properties).
A network error occurred but a TCP connect from a remote location is successful.
Monitor has status 21, 90, 95, or 6061 – these are platform errors and they do not affect monitor availability.
The recipient’s alert trigger has not yet been reached (the Alert after this # errors option).
The recipient’s consecutive alert limit has been reached (the Stop alerting after this # alerts option).
A “clear” notification is not sent if the recipient has them disabled (the Alert whenever an error clears option).
The monitor does not have performance thresholds set. You can set them in the monitor settings. For details, see Performance Alerts.
The recipient has performance alerts disabled.
Successive alerts are not sent if the recipient has Repeat successive performance alerts disabled.
Warnings are not sent if the recipient is configured to get errors only.
Performance alerts are sent only to email, email to wireless device and PagerDuty, and are not sent to other recipients.