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Flexible server monitoring

Introducing Simon 5!

Simon version 5 is now available. It is a massive update, introducing a much-requested feature: syncing the Simon data between multiple Macs, plus a Simon Status service, a Link Checker filter, improved Find filter, iMessage and Speak Error notifiers, a new app icon, and much more.

Important: please note that Simon 5 requires a minimum of macOS 10.12 (Sierra), and is a paid upgrade from Simon 4. Purchasers since September 1, 2020 automatically get a version 5 license (that also works in previous versions).

Read the Simon What's New page for details.


The feature I really need - unless I'm just missing it? - is a way to model dependencies. The biggest case is that I don't want to get alerts for web sites I monitor when my home internet connection has a problem. In nagios I make external services dependent on my router ping, dns server ping, and check and I'd like to be able to do the same thing in Simon.

David Sinclair's picture

Re: Dependencies

Simon handles local internet outages automatically. Before each check, it checks that it can access one of two popular domains ( and, if I recall correctly), and if not, goes into an offline mode until the connection is restored.

You can disable this feature on a per-test basis via the checkbox to allow checking when offline (e.g. for local-only tests, or if you want to be alerted when your local internet is down).