realm::sync::ProtocolError Bad changeset (UPLOAD)




Since yesterday morning we’ve started getting ‘bad changeset’ errors on all servers/apps while connection to our cloud instance.

Connection[1]: Session[1]: Received: ERROR(error_code=212, message_size=22, try_again=0)
Connection[1]: Disconnected
Session {} { name: ‘Error’,
message: ‘Bad changeset (UPLOAD)’,
isFatal: true,
category: ‘realm::sync::ProtocolError’,
code: 212,
userInfo: {} }

Any ideas how this could be resolved? I’ve already created a support ticket, but since it is the weekend, i’m worried this won’t get looked at till Monday (or at all).

This seems to be related to some schema changes. This is happening on development env where an existing object was modified to include a new field. The reason i think this might be the problem is because realm studio is showing the schema object without the new field.

I’ve tried to change the field, remove it, add default value, add different fields, nothing seems to work, it would seem the cloud instance is now in a broken state and won’t recover.

Any ideas would be appreciated.

Best regards,


I’ve identified the problem. One of the existing fields was updated to be ‘optional’, hence the realm cloud was not able to reconcile the old schema with the new schema.