Although two ports on each system are configured for remote copy port group 1, only one  Ethernet port in each system actively participates in the IP partnership process. This  selection is determined by a path configuration algorithm that is designed to choose data  paths between the two systems to optimize performance.  The other port on the partner node in the I/O Group behaves as a standby port that is  used if a node fails. If Node A1 fails in System A, IP partnership continues servicing  replication I/O from Ethernet Port 2 because a failover port is configured on Node A2 on  Ethernet Port 2.  However, it might take some time for discovery and path configuration logic to reestablish  paths post failover. This delay can cause partnerships to change to  Not_Present  for that  time. The details of the particular IP port that is actively participating in IP partnership is  provided in the  lsportip  output (reported as  used ).  This configuration has the following characteristics: Chapter 11. Advanced Copy Services  585 Figure 11-100 Multinode systems single inter-site link with only one remote copy port group – Each node in the I/O group has the same remote copy port group that is configured.  However, only one port in that remote copy port group is active at any time at each  system.  – If the Node A1 in System A or the Node B2  in System B fails in the respective systems,  IP partnerships rediscovery is triggered and continues servicing the I/O from the  failover port. – The discovery mechanism that is triggered because of failover might introduce a delay  where the partnerships momentarily change to the  Not_Present  state and recover. GLYPH<SM590000> Two 4-node systems in IP partnership over a single inter-site link (with failover ports  configured), as shown in Figure 11-100 (configuration 3).