How to Remove, Clean Up, and Reinstall rhevm-reports

Issue

• A mistake was made entering in the password during rhevm-dwh-setup and rhevm-reports-setup. Running rhevm-cleanup does not "reset" the rhevm-dwh or rhevm-reports installations, only the RHEV-M base installation which is not desired on a production RHEV environment.
• Attempting to run rhevm-dwh-setup or rhevm-reports-setup after running rhevm-cleanup does not present the opportunity to reconfigure either of these services from scratch.

Some common issues observed due to incorrect procedure followed OR none of the procedure followed for upgrading the reports are as below:
1. Unable to upgrade: Cannot connect to Reports database using existing credentials
2. RHEV Report portal doesn't work
3. Upgrade from 3.3 to 3.4 - Reports are not working
4. when install report for rhev, it display Failed while importing reports
5. engine-backup failed

/usr/bin/engine-backup --scope=all --mode=backup --log=/disk1/rhev_backup/backup.$(/bin/date +%Y%m%d%H%M%S).out  --file=/disk1/rhev_backup/backup.$(/bin/date +%Y%m%d%H%M%S).tar.bz2

with error :

2014-06-12 09:27:37 23531: Start of engine-backup mode backup scope all file /disk1/rhev_backup/archives/engine_20140612_09:27.bz2
2014-06-12 09:27:37 23531: Backing up:
2014-06-12 09:27:37 23531: Generating pgpass
2014-06-12 09:27:37 23531: Creating temp folder /tmp/engine-backup.cDTix814MV/tar
2014-06-12 09:27:37 23531: - Files
2014-06-12 09:27:37 23531: Backing up files to /tmp/engine-backup.cDTix814MV/tar/files
2014-06-12 09:27:37 23531: - Engine database 'engine'
2014-06-12 09:27:37 23531: Backing up database to /tmp/engine-backup.cDTix814MV/tar/db/engine_backup.db
2014-06-12 09:27:39 23531: - DWH database 'ovirt_engine_history'
2014-06-12 09:27:39 23531: Backing up dwh database to /tmp/engine-backup.cDTix814MV/tar/db/dwh_backup.db
pg_dump: [programme d'archivage (db)] la connexion à la base de données « ovirt_engine_history » a échoué : FATAL:  authentification Ident échouée pour l'utilisateur « engine_history »
2014-06-12 09:27:39 23531: FATAL: Database ovirt_engine_history backup failed

If you would like to reinstall rhevm-reports, but keep all data warehousing (dwh) information intact, please follow one of these articles:

• For RHEV 3.1/3.2, follow this article
• For RHEV 3.3, follow this article.