Hi @Akhil S Naik, Thank you so much for your answer. Due to your support, I got out of this trouble but getting into another one. What I did is that I made a backup of ambari.properties (as mentioned is this document: https://docs.hortonworks.com/HDPDocuments/Ambari-2.7.1.0/bk_ambari-upgrade-major/content/preparing_to_upgrade_ambari.html). So I copy those following lines from the backup file into the new one: server.jdbc.connection-pool=internal server.jdbc.database=postgres server.jdbc.database_name=ambari server.jdbc.postgres.schema=ambari server.jdbc.user.name=ambari server.jdbc.user.passwd=/etc/ambari-server/conf/password.dat After that, the upgrade proceeds a little bit further, then produces the following error: Traceback (most recent call last): File "/usr/sbin/ambari-server.py", line 1060, in <module> mainBody() File "/usr/sbin/ambari-server.py", line 1030, in mainBody main(options, args, parser) File "/usr/sbin/ambari-server.py", line 980, in main action_obj.execute() File "/usr/sbin/ambari-server.py", line 79, in execute self.fn(*self.args, **self.kwargs) File "/usr/lib/ambari-server/lib/ambari_server/serverUpgrade.py", line 262, in upgrade retcode = run_schema_upgrade(args) File "/usr/lib/ambari-server/lib/ambari_server/serverUpgrade.py", line 162, in run_schema_upgrade upgrade_response = json.loads(stdout) File "/usr/lib/ambari-server/lib/ambari_simplejson/__init__.py", line 307, in loads return _default_decoder.decode(s) File "/usr/lib/ambari-server/lib/ambari_simplejson/decoder.py", line 335, in decode obj, end = self.raw_decode(s, idx=_w(s, 0).end()) File "/usr/lib/ambari-server/lib/ambari_simplejson/decoder.py", line 353, in raw_decode raise ValueError("No JSON object could be decoded") ValueError: No JSON object could be decoded I see that this problem is some kind of similar to the old one but I cant figure out how to solve it. Can you tell me how I can understand and solve these kinds of problem or how I can investigate and search for solution for it. Thank you so much for your help. P/s: For your question, I'm upgrading ambari from version 2.6 to 2.7. ... View more