Node  testnode3  is again registered on hdisk3 and hdisk4 when it has successfully rejoins  testnode4 to form a cluster. You must perform a restart of cluster services on testnode3. This section provides a list of changes that are associated with the split and merge policies  that are introduced in PowerHA V7.2.1 for AIX V7.2.1: 346  IBM PowerHA SystemMirror V7.2.3 for IBM AIX and V7.2.2 for Linux GLYPH<SM590000> An entry is added to the  Problem Determination Tools  menu for starting cluster services  on a merged node after a cluster split. GLYPH<SM590000> Changes were added to  clmgr  for configuring the split and merge policy. GLYPH<SM590000> The action plan for the split and merge policy is configurable. GLYPH<SM590000> Split and merge policies are configured as a whole instead of separately. These options  can also vary a bit based on the exact AIX dependency. GLYPH<SM590000> Split and merge policies are configurable for all cluster types when AIX is at Version  V7.2.1, as summarized in Table 9-1. Table 9-1 Split and merge policies for all cluster types 9.4 Changes in split and merge policies in PowerHA V7.2.1 Cluster Type Pre- AIX 7.2.1 AIX 7.2.1 Split policy Merge policy Split and merge policy Standard Not supported None-Majority TB (Disk)-TB (Disk) TB (NFS)-TB (NFS) Manual-Manual Stretched None Majority TieBreaker TieBreaker Linked None Majority TieBreaker TieBreaker Manual Manual