MySQL Replication Failed

tom — Sun, 26 Apr 2009 12:40:28 +0000

I wanted to replicate a MySQL-Database using the integrated Master -> Slave mechanism.

Master-System: openSUSE 10.2, MySQL 5.0.26
The Slave-Setup: openSUSE 11.1, MySQL 5.0.67

This is quite easy to setup usually. This time, I almost had a nervous breakdown.
On the slave side the replication just didn’t start. The logfile showed these errors:
090421 20:49:28 [ERROR] Slave: Error 'Duplicate entry '790233' for key 1' on query. ... 090421 20:49:28 [ERROR] Error running query, slave SQL thread aborted. Fix the problem, and restart the slave SQL thread with "SLAVE START". We stopped at log 'mysql-bin.000008' position 30408893

As checking the database and making sure that there were no “duplicate entries”,
did not bring up any results, I found something curious (after hours and hours).

On the Master-System:

mysql> SHOW MASTER STATUS; +- - - - - - - - + - - - - - + - - - - - - - + - - - - - - - - -+ | File | Position | Binlog_Do_DB | Binlog_Ignore_DB | +- - - - - - - - + - - - - - + - - - - - - - + - - - - - - - - -+ | mysql-bin.0001 | 10034 | mydb,mydb | | +- - - - - - - - + - - - - - + - - - - - - - + - - - - - - - - -+
Why is the database listed two times? In the configuration it’s only used one time:

binlog-do-db = mydb

After spending some time on google, I found the reason:
http://bugs.mysql.com/bug.php?id=20748
It’s a bug : / MySQL (in that version) is reading the configuration file twice.

If installing a newer version is not possible, you can use this workaround:
Start MySQL with the option --defaults-file=/etc/my.cnf
This advices MySQL to ONLY use this config file.

PAM-Authentication & MySQL (v5) / b1gMail

tom — Thu, 15 Mar 2007 15:46:23 +0000

Enviroment:

SuSE Linux 10.1
- pam-0.99.3.0-29.3, pam-modules-10.1-7
- postfix-2.2.9-10
- mysql-5.0.18-20.8, mysql-client-5.0.18-16

I was trying to implement SASL-authentication via PAM (which is using a mysql-backend) in a postfix installation.
Output from maillog:

postfix/smtpd: warning: SASL authentication failure: Password verification failed postfix/smtpd: warning: [x.x.x.x]: SASL PLAIN authentication failed

Checking the syslog:

saslauthd: pam_b1gmail: cannot connect to mysql database (Access denied for user 'xx'@'localhost' (using password: YES)) saslauthd: DEBUG: auth_pam: pam_authenticate failed: Permission denied saslauthd: do_auth : auth failure: [user=xx] [service=smtp] [realm=domain.tld] [mech=pam] [reason=PAM auth error]

Reason:
The PAM module is using a deprecated way to connect to the MySQL-DB.

Solution:
Set the MySQL-Password to OLD_PASSWORD:

SET PASSWORD FOR user'@'localhost' = OLD_PASSWORD('password');

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MySQL Replication Failed

PAM-Authentication & MySQL (v5) / b1gMail