Problem:
the Hana system replication standby machine cannot take over the host, and the Hana host can be used normally.

The following errors are reported in the trace file:
SR_dataaccess DisasterRecoverySecondaryImpl.cpp(00882) : Error occurred during connect to primary: exception 3000301: Connection could not be established

Solution:
this problem is generally caused by a network problem between the active and standby computers
for the above error reports, you can first check whether the 3xx00-3xx99 port segment of the standby machine to the host is occupied or blocked.