How element consolidation can cause SYNC problems.

Document ID : KB000051834
Last Modified Date : 14/02/2018
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Description

Under certain circumstances consolidation can cause element synchronization error messages when moving the consolidated element to the next stage.

Solution

How element consolidation can cause SYNC problems.

Under certain circumstances consolidation can cause element synchronization error messages when moving the consolidated element to the next stage.

Sync problems will occur when an element has been moved up the map with option bypass element delete and when later a number of updates are made to the same element which lead to element consolidation.
Before element consolidation Endevor knows that the source and target element are synchronized, but after consolidation has occurred Endevor can no longer determine whether the elements are synchronized and will issue SMGR116 or SMGR117 messages when moving the element.

Recovery from this problem is possible using the following methods:

  • Delete/re-add the element.
  • Use the SYNC option on move actions, after inspection of the source code, ensuring that the source element is in sync with the target element.


Ideally this problem should be avoided, using one of the following methods:

  • Ensure the move is always done with delete behind of the source element.
  • Ensure no delta consolidation occurs in the lower stages, by activating age managed delta retention.

The following section gives a detailed description of how SYNC works and why the problem can occur after consolidation.

An overview of how sync works:

Endevor's synchronization checks are based upon the comparison of the date and time stamps of delta levels in hundredth's of seconds. When an element is modified in a lower stage, Endevor fetches the last delta level of the element in the next higher stage. The delta level date/time stamp of this fetched element is the same as the last delta level date/time stamp of the fetched element.
When modifications are made in the lower stage, each modification gets its own date/time stamp.
When the element is moved, Endevor compares the lowest timestamp of the source element with the highest timestamp at the target and when they match Endevor knows that the elements are synchronized. If the timestamps do not match, Endevor will search for a group of matching delta levels at the source level and compare them with the last delta levels at the target. If a matching group exists the elements are synchronized. The group tests are needed for move actions without delete behind.

The impact of consolidation after a move without delete behind:

When an element is moved without deleting the source element, Endevor depends on groups of delta levels to be in sync. When consolidation occurs, the very first delta level at the source will remain unchanged, but the second delta level, the consolidated level, will get a date/timestamp that will no longer match the last delta level at the target. As a result, the testing of groups of delta timestamps will not find a matching group and thus Endevor cannot determine whether the elements are synchronized or not. The result is a sync error.

Below follows a simplified example which illustrates the case. Note that the timestamps are listed in hh:mm format, although the actual validations compare up to 100th of a second.

The element in stage-2 after adding 2 versions in stg1 and move with history, without delete behind:

  VV.LL            User     Date    Time  Statements Inserts Deletes Sync 
- ----- ---------- -------- ------- ----- ---------- ------- ------- ---- 
_ 01.00            VANJA01  04MAY10 07:09          1      0       0       
_ 01.01            VANJA01  04MAY10 07:10          2      1       0       

The element in stage-1 after one more update in stage-1:

  VV.LL            User     Date    Time  Statements Inserts Deletes Sync 
- ----- ---------- -------- ------- ----- ---------- ------- ------- ---- 
_ 01.00            VANJA01  04MAY10 07:09          1      0       0       
_ 01.01            VANJA01  04MAY10 07:10          2      1       0       
_ 01.02            VANJA01  04MAY10 07:11          3      1       0      

The elements in stage1 and stage2 remain synchronized because the group of levels 0100 and 0101 in stage1 match the last two delta levels in stage2.

The element in stage-1 after two more updates in stage-1 and subsequent level consolidation:

  VV.LL            User     Date    Time  Statements Inserts Deletes Sync 
- ----- ---------- -------- ------- ----- ---------- ------- ------- ---- 
_ 01.00            VANJA01  04MAY10 07:09          1      0       0      
_ 01.01            VANJA01  04MAY10 07:12          4      3       0   C  
_ 01.02            VANJA01  04MAY10 07:12          5      1       0      

Endevor will no longer find a match between any delta level at the source with the last delta level at the target. As a consequence it cannot determine whether the elements are synchronized, leading to the out of sync notification SMGR116/SMGR117.