I have an R610 that has been giving us issues. It seems like the AP just disappears for a minute or two and then comes back. It doesn't get flagged or set an alarm. That being said if I look at the Event log for the offending AP I see the usual traffic but then nothing will be logged for the period that the AP is "On Vacation". This is a very active AP other wise with devices roaming in and out constantly. The 2 to 3 minute periods where no events are logged are highly suspect. I'm thinking this is probably hardware at this point, which gets me to my next question.
I have a spare R600 I want to swap out with the R610. It's been on the shelf for a long time so I updated it to the latest firmware (184.108.40.206.2005) and pointed it at our SZ-100 (set scg ip <ip address)>) but it doesn't want to join. I see no indication that the SZ has been in contact with the R600. Get scg list the Server correctly and shows SCG is enabled but that's about it.
My SZ-100 is at 220.127.116.11.317
Any pointers would be great.
The fact that is appears and disappears for a minute or so would push me to look at a Layer 2 /Layer 1 problem.
Hopefully you are using a fully managed switch, check the logs on the switch to see if you can see any events on the port it is connected to