The mode is depend on your DB parameter DRINTERVAL and DRAUTO.
DRINTERVAL is specified interval of sending logical log when change ocurr.
if you set -1,DB is alway synchronized.
DRAUTO is specified DB behavior when disaster happen on Primary site.
There are 0,1,2 (depend on IDS version).
0 signifies OFF = Do not automatically switch the server type in the HDR environment.
1 signifies RETAIN_TYPE = Automatically switch secondary to standard during an HDR failure. Switch back to secondary when restarting HDR.
2 signifies REVERSE_TYPE = Automatically switch secondary to standard on an HDR failure. Switch to primary (and switch original primary to secondary) when restarting HDR.
you can follow this link to find out
http://publib.boulder.ibm.com/infoce.../v10/index.jsp