602 Implementing the IBM Storwize V7000 with IBM Spectrum Virtualize V8.2.1
If your investigations fail to resolve your remote copy problems, contact your IBM Support 
representative for a more complete analysis.
Note: With Consistency Protection enabled on the MM/GM relationships, the system tries 
to resume the replication when possible. Therefore, it is not necessary to manually restart 
the failed relationship after a 1720 error is triggered.