The viewpoint-admin user is the out-of-the-box administrative user that allows you to log into Viewpoint to set up everything else. To change it run the following on the viewpoint host and substitute the new password for p@ssw0rd.
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[root]# echo -n 'p@ssw0rd' | /opt/viewpoint/bin/viewpoint makehash
pbkdf2_sha256$20000$Io5C7Jd2FPTy$dBoikb0hsZQlgY2NTBYSgWU8YSHNY8+/OhvTIs/g4oc=
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DON'T FORGET TO ADD THE -n OPTION TO echo!!!!!!!!!! If not you'll have a newline included in your password. This took me a while to track down
Copy the output line that starts with pbkdf2, and paste it in the password field of /opt/viewpoint/etc/viewpoint.cfg
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[root]# vim /opt/viewpoint/etc/viewpoint.cfg
username = viewpoint-admin
password = pbkdf2_sha256$20000$Io5C7Jd2FPTy$dBoikb0hsZQlgY2NTBYSgWU8YSHNY8+/OhvTIs/g4oc=
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Restart Viewpoint
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[root]# systemctl restart httpd
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