The device is pingable. HTTPS as well as the enterprise manager client would not allow login.
SonicWall tech support spent about three hours remotely deleting data and log files. Then they rolled back the firmware and finally were able to login.
I have not been back on site to test yet, so I'm not positive that it's resolved.
However, a couple of things that I've learned/revisited during this experience.
1. DO NOT EVER let the CDP drives fill completely. There is NO WAY an end user can fix the problem, and if you don't have a support contract, you're SOL.
2. If you fill a Volume Quota, that backup process simply stops. It doesn't delete old versions of files dynamically. You have to delete ALL the old versions of files, thus erasing all of your backups. I had the tech support person from Sonic change the number of old versions that the CDP stores. I cut it in half. Again, this is a setting that should be, but is not, user configurable. You need tech support to connect to the box and make the change.
I like the concept behind the CDP, but even after having been out for a year, the firmware is still at Beta level, in my opinion.