Hi, even I am facing the same trouble when trying to load Ambari web page, it shows 502 error.   It was working fine 2 days back but the error is showing from today when I tried to login in the morning. I have tried all the replies stated above, none worked. I will be grateful if someone can resolve this issue at the earliest.   Many Thanks ... View more

@divya_thaore  1. If you are starting service via Ambari / Cloudera Manager UI then check the operation logs which are displayed in UI while you start the service     Please check for any errors in the logs clicking the service operational logs. 2. If you do not see any operational logs or any operation triggerred while you start/restart service then kindly restart agent service once [ambari agent/cloudera-scm-agent] 3. Else please check logs from cli as suggested by @Shelton    If you still need help please revert. ... View more

Thanks.. It works from SSH.. But I want to do it from ambari UI. ... View more

What is your current Ambari version? A. For Ambari 2.6.2.2 and previous versions, follow these steps in the Ambari host: 1. Log in to Postgres database # 'psql -U ambari ambari' 2. Enter password for 'ambari' database. Default is 'bigdata'. Can be found in this file: /etc/ambari-server/conf/password.dat 3. In PSQL run the below query: update ambari.users set user_password='538916f8943ec225d97a9a86a2c6ec0818c1cd400e09e03b660fdaaec4af29ddbb6f2b1033b81b00' where user_name='admin' 4. Quit PSQL 5. Restart Ambari server ambari-server restart This will reset the admin account back to the password of 'admin'. Steps taken from: https://community.hortonworks.com/questions/449/how-to-reset-ambari-admin-password.html B. For Ambari 2.7.x you can follow steps mentioned in this article: [Ambari-2.7.0] How to Reset Ambari Admin Password from Database if you forget it ? Hope it helps. ... View more

@Divya Thaore If you are on HDP 2.6.x the login using credentials: root / hadoop and you get the prompt Did you run this command after ambari-admin-password-reset HTH ... View more

@Geoffrey Shelton Okot yes through sandbox from HW. ... View more

@Divya Thaore As you mentioned that your system total RAM is: 8GB and you have allocated 4GB to sandbox. . Sandbox Minimum Requirement: In order to run components without issue, Minimum 8GB RAM you should have dedicated on your 64 bit OS to run the Sandbox without any issue. Less RAM allocation might cause a very slow startup of Sandbox and might cause Hung Or Network Service failure. Example: If your Laptop has 16GB RAM then you can allocate 8GB to your Sandbox VM to use it properly. ... View more

Also there are too many alerts automatically after starting,,.. So is it normally started or abnormally ? @Jay Kumar SenSharma ... View more