Above the exception is when connecting to my, very strange, because DB2 USES for such a long time have never seen this problem, the single from the perspective of the exception message is obviously validation fails, the DB2 connect to a user name and password problem, the problem is why such a problem, when the user name and password are correct.

Study found that after is the system differences, the password can’t be in clear text mode is stored in the system, are saved after through the corresponding encryption algorithm, DB2 USES a SHA256 encryption, and a lot of high version of the Linux the default encryption algorithm is the SHA512, such system to create DB2 user password by SHA512 stored in the system, the connection to DB2 by SHA256 password passwords in encrypted and stored in the system, the result is, of course, failure, the solution is as follows:

Open the /etc/pam.d/system-auth file, find the second line of passwd configuration, change sha512 to Sha256, and save;

Rerun the passwd DB2 user and set the password;

Success;

This will replace the system encryption method with SHA256 and then update the saved password.