I had a problem with my iMac which had mounted on it via afp several volumes of my NVX. I rebooted the mac and tried to re-connect to the server, only to get the standard error above (ie using a temporary CNID DB, read-only mode).
From reading other posts, the suggested solution is to delete/move .AppleDB on the affected volumes - however I cannot get write access via any method I have tried (ssh, sftp).
I cannot change my cifs access to enable write access, since the web interface will not give me the share listing screen. I have tried re-installing the firmware (4.2.21), which hung (for ~1 hour) during the reboot, before I held the power button. On reboot I still have the same connection problem.
To add to the fun, I cannot seem to download the logs either.
Best not to keep on trying to fix things yourself. You're only likely to make things worse. Support does have a means of remotely logging into units (they can provide you with instructions on how to give them access if it comes to that).
Whether it was something I did, or a consequence of the error that occurred I don't know. But the Netgear Tech support managed to get my NAS back up with some data loss due to a "massive file system corruption". I have backups of my most critical data, so didn't lose too much, and, after a factory reset, all seems ok.
I am most concerned by what I did/what happened to cause data loss. And am very uncertain what cause the original CNID DB error, and what can be done to avoid it in the future.
Improvements have been made to Netatalk (AFP/Time Machine service) over time and as a customer of NetAFP which develops Netatalk, NetGear does a good job of updating Netatalk in firmware updates.
Whatever caused the problem occasionally things like this can happen. You're unfortunate that it's happened on your system. It's one of many reasons that backups are important. See Preventing Catastrophic Data Loss
