QUESTION:
Why, after a migration from WinCC V4.x to WinCC V5 SP2, can I no longer page in my data from the storage data medium?

ANSWER:
"Storage" records its activities in an internal logbook. It contains, for example, records of time intervals, activities (delete/export) and data medium names/numbering. For paging in, "Storage" needs information from the logbook, otherwise paging in is not possible. With time, the logbook becomes increasingly larger through the constant deleting and exporting. Since it contains quasi Runtime information, the logbook was kept in the Runtime database until version V4.x.
If the Runtime database was deleted for whatever reason, the "Storage" logbook was also lost.

As a first counter-measure, the "Update logbook from data medium" function was introduced in version V4 (Storage dialog, "Page In" tab). This at least permitted exports to be reconstructed. Nevertheless it was no longer possible to trace data deletion.
With WinCC version 5 SP2, the logbook was relocated to the CS database. This means that the logbook is retained even if the Runtime database is deleted. The consequence is that, after migrating a project from version V4 to version V5 SP2, Storage finds an empty logbook. There is no automatic transfer from the Runtime database to the configuration database, because from the technical point of view there is no guarantee that there is a complete logbook in the Runtime database; the database might have already been replaced once.

In order nevertheless to be able to page in old data under version V5 SP2, which was previously exported under version V 4, the logbook must first be reconstructed via "Update logbook from data medium" before the first export under version V5 SP2 and thus before the first entry in the logbook.
If the old data medium remains in the driver, the existing exports on this data medium might be overwritten. After migration to version V5.x SP2 you must always continue you work with a new data medium.

Warning:
If upon migration you do not execute the "Update logbook from data medium" function before version V5 SP2 exports for the first time, then "Storage" will in fact continue to number the data media consecutively with n+1, n+2 etc. Reconstruction of the logbook of old V4.x data media would be possible, but each attempt to page in from these old V4.x data media would be rejected wit the error message
"Archive: invalid parameter".

Remedy:

1. After migrating the project from WinCC V4 to V5 SP2 set the "No Action" option in the "Repeat" group via the "Configuration" tab in the Storage dialog. This means that there is no definitely no export when the Runtime is activated. You must not remove the "ArchServ.exe" file from the startup list.
2. Activate Runtime.
3. Insert the data media created with V4 one after the other into the drive.
4. In the Storage dialog, in the "Page In" tab, click the "Update logbook from data medium" button for each entry. During updating you get the message "Progress: archive logbook from data medium". This box might remain for a while on the screen, depending on how many export intervals are stored on the data medium.
5. Wait for the completion message: "Updating of the logbook from the archive data medium successfully completed".
6. This new information from the data medium is not displayed automatically in the window. If you want to see it to check, then change the view from "Messages" to "Measured Value Archives" or click the "Update" button at the top right.
7. Remove the last data medium from the drive.
8. Insert a new, empty data medium into the drive and set it up ("Storage dialog > Data Medium > Create Archive Data Medium"). "Storage" now automatically assigns the next highest data medium number.
9. Thus the logbook and the available data match.
10. Now you can set the original "Export" action again for Alarm, Tag and Report in the Storage dialog, "Configuration" tab, "Repeat" group, so that time-controlled exporting can take place as usual.

Note:
Through the improvements in version V5, you can notice the difference in versions when observing the message pictures. With version V4, for example, in the operator activities list there was no entry in the "Origin" column or in the "Operation" column for I/O field operations. With version V5 these entries are made.
When paging in such operation messages under version V5 differences can be noticed depending on whether the messages have been created originally in version V4 or first in version V5:

• For messages already created in version V4, you can display the "Operation" column, but the "Origin" column continues to remain empty.
• For message first created in version V5, both columns are displayed even after paging in.

If through paging in old V4 messages appear alongside new V5 message on a message page, then you get the impression that one and the same type of message is being displayed in two different ways.
This effect also occurs with other message types such as control system messages. The effect is due to the message system itself. From the point of view of "Storage", the format of the export data has not changed from version V4 to version V5. The exported files simply return the contents of the database tables (Alarm Logging and Tag Logging).

Keywords:
Archiving