[db2inst2@localhost ~]$ db2 TAKEOVER HADR ON DATABASE MYDB3
SQL1770N Takeover HADR cannot complete. Reason code = "5".
[db2inst2@localhost ~]$ db2 ? SQL1770N
5 Activate the standby database, then issue the takeover command.
[db2inst2@localhost ~]$ db2 connect to mydb3
SQL1776N The command cannot be issued on an HADR standby database. Reason code = "1".
[db2inst2@localhost ~]$ db2 takeover hadr on database mydb3 by force
SQL1770N Takeover HADR cannot complete. Reason code = "5".