Simon icon Simon
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.

Kernel panics


Yesterday, my Mac Mini Server running SL 10.6.8 rebooted because of a Kernel Panic. The same thing happened 2 weeks ago. In both cases, the .panic says that "Simon" was the BSD process name corresponding to the current thread. I'm not really pointing a finger at Simon since lots of things can go trigger a Kernel Panic, but running Simon is the only major modification I made to this server during the last month, which has been running quite well for months. The failures occurred on a Saturday and on a Sunday, at different times, so Simon may have been the only "active" process at this time. This server is lightly loaded.

My checks use the following services : Ping, Web (HTTP), IMAP and DNS. I know that Ping performs its check through another process, so the culprit maybe one of the other ones.

So, has anyone seen this kind of behavior before ? I could post the .panic files but I'm not sure that this would be really useful.

Now for some background: I am running Simon 3.1.1 since the version 3.2 generates lots of spurious failures every 30 minutes (see my other post) and I'm using a single non-Apple Kexts :

I'll now try to run Simon 3.2, with a lighter load (checks every 5 minutes instead of every minute).

Best Regards,