My backup is failing, becasue SME server thinks root@localhost has one password, and MySql thinks it is something else.
No, your backup is failing because YOU changed the mysql root password.
This has been posted MANY MANY MANY times on these fora.
DON'T EVER CHANGE THE MYSQL ROOT PASSWORDThe default password is a random 72 char hash system generated string.
Version 6.X was fairly easy to restore the password but 7X is much harder.
Since you have changed it to make phpmyadmin work then you can change it back with phpmyadmin but phpmyadmin will no longer work afterwards. it is located in /root/.my.cnf
Do the following:
1-use your installed phpmyadmin and change the password back. Be VERY VERY careful because if you don't get it right then nothing will get you in except a sequence that is outlined in the bug tracker.
2-type mysql at the command prompt to make sure you changed it right.
3-Remove whatever version of phpmyadmin that you installed and install the correct one from here:
http://mirror.contribs.org/smeserver/contribs//dmay/smeserver/7.x/smeserver-phpmyadmin-2.6.4-pl4.dmay.noarch.rpmRemember, before you install anything on your server, make sure it has been tested on SME.