We have noticed that tags will display in our Vision project as grayed out or red sometimes. This problem seems pretty weird because it has various characteristics. First of all it is not all the tags and second it is not always the same tags. Then there is other inconsistent behavior, the tag will show red/grey in the client, but fine in the designer sometimes. Or it will show red on the client, designer, and tag browser, but on the tag status page of the gateway it will show the tag value changing and updating. The only short term remedy we have is to fail over the master gateway and then force it fail back seems to get the tags to start updating again. I have noticed the following message in the console, but I am not sure if it is related or not.
Subscription path model set detected to be out of sync. Will re-synchronize.
Another thing I have observed is that s tag I have setup that is set to an expression of time and its scan class updates every second. When things seem to be working correctly you can see the value updating in the designer, but when things are not working this tags values does not change in the tag browser except when you manually refresh the tag tree.
We are running 7.9.6 on the front end and 7.9.5 on the backend.