New Instalation

I just installed Perona XtraDB cluster on Centos 7, I am trying to login for the first time to mysql using the following command:
mysql -u root and I am getting this error ERROR 1045 (28000): Access denied for user ‘root’@‘localhost’ (using password: NO)
I also tried mysql -u root -p and I am getting ERROR 1045 (28000): Access denied for user ‘root’@‘localhost’ (using password: YES) I do not understand the problem

Hi! i know this post has month here, but i would like to add my answer just in case someone has the same error.
If you follow the tutorial that Percona has kindly write for us (https://www.percona.com/doc/percona-xtradb-cluster/LATEST/install/yum.html#yum) you will see in step 5 this line.
sudo grep ‘temporary password’ /var/log/mysqld.log There is the solution to your problem. And if you keep doing the tutorial you will know how to change that password to the on that you like.

Hi @furbaez

mysql -u root and I am getting this error ERROR 1045 (28000): Access denied for user ‘root’@‘localhost’ (using password: NO)

=> above command  ‘-p’ is missing (for password) hence it is directly trying to login without password.

I also tried mysql -u root -p and I am getting ERROR 1045 (28000): Access denied for user ‘root’@‘localhost’ (using password: YES) 
=> Here the password is incorrect.