MySQL daemon failed to start - mysql

MySQL won't restart when I try "service mysqld restart"because I'm using this part in my.cnf
master-host = [private-IP-of-db01]
master-user = [replication-username]
master-password = [replication-password]
master-connect-retry = 60
when I comment out these parts! MySQL restarts fine. Why is that so? Also I have to include these lines in my.cnf because of master slave replication and I can't omit them out.

Usually master host information on the slave mysql server is stored in "master.info" file and maintained there. You may want to start mysql without adding the configuration to your "my.cnf" file, the only configuration you may want to add is a "server_id" , Once mysql is up and running, you should setup slave with 'change master command....'.

Related

MySQL - PhpMyAdmin Replication Reset Master Configuration to retrieve server-id

MySQL server + phpmyadmin
On the replication tab, it looks like someone already configured the master replication:
However, I do not see the following lines in my.cnf, which should have been added at the time the master was configured :
server-id=*****
log-bin=******
log-error=*****
How do I retrieve those values? Or how do I reset the master configuration so that I can perform the whole process myself (I also want to select/ignore new databases)?
I finally managed to solve my issue.
Note: The server-id is just a unique identifier that you can chose.
I had to enter those lines in the master's my.cnf file:
#master my.cnf
server-id = 1
log_bin = /var/lib/mysql/mysql-bin.log
binlog_do_db=database1
binlog_do_db=database2
binlog_do_db=database3
binlog_do_db=database4
binlog_do_db=database5
And those lines in the slave's my.cnf file:
#slave my.cnf
server-id = 2
replicate-do-db=database1
replicate-do-db=database2
replicate-do-db=database3
replicate-do-db=database4
replicate-do-db=database5
Then on the slave server's phpmyadmin go to replication tab and click Stop SQL Thread only and Stop IO Thread only

MySQL replication - Slave won't start mysql service

I'm testing MySQL replication on two virtual machines with VirtualBox running Debian 8.2.
Following tutorials, this is how I set the slave's /etc/mysql/my.cnf:
server-id = 2
master-host = 192.168.56.101
master-connect-retry = 60
master-user = slave
master-password = 123
replicate-do-db = base1
replicate-do-db = base2
relay-log = /var/lib/mysql/slave-relay.log
relay-log-index = /var/lib/mysql/slave-relay-log.index
However, doing so also won't let me start mysql. When I run /etc/init.d/mysql start, it fails. These are the two errors that appear on the logs:
error: Can't connect to local MySQL server through socket '/var/run/mysql/mysqld.sock' (2)
Failed to start LSB: Start and stop the mysql server database daemon
Commenting the master-zzz lines allow mysql to start without a hitch.
The virtual machines can see each other and ping without loss. I've tried changing the my.cnf's master-user and password, as well as creating different replication slave users on the master server, to no avail. What am I doing wrong?
Well, turns out the tutorials I was following were a bit outdated. These are the final configurations of my.cnf files:
#master
bind-address = 0.0.0.0
server-id = 1
log-bin= /var/log/mysql/mysql-bin.log
#slave
server-id = 2
Instead of setting the slave's my.cnf, I used the mysql console:
CHANGE MASTER TO master_host='master_ip', master_user='slave', master_password='slavepass';
As per this manual's instructions: https://downloads.mysql.com/docs/mysql-replication-excerpt-5.0-en.pdf

Mysql slave gets ruined after a restart

Please help!
I set up a master-slave replication based on the GTID mechanism.
The replication works OK, until a mysqld restart happens on slave. Then the mess begins...
After such a restart, I can not restore the replication.
When issuing a "START SLAVE" command I get the following an error message:
ERROR 1794 (HY000) at line 1: Slave is not configured or failed to
initialize properly. You must at least set --server-id to enable
either a master or a slave. Additional error messages can be found in
the MySQL error log.
Needless to say I did set server-id in my.cnf (see below).
In /var/log/mysqld.log file, I found the following error message:
[ERROR] Error creating master info: Multiple replication metadata
repository instances found with data in them. Unable to decide which
is the correct one to choose.
[ERROR] Failed to create or recover replication info repository.
I can not understand what have I done wrong.
The communication between master and slave is ssl-tunneled through stunnel, but I don't think this is a relevant fact, since until a restart everything works right.
The only way I found to re-establish the replication (after mysql restart) is to manually delete the mysql data files, and then load again the dump file imported from the master. (I use mysqldump). This is of course unreasonable.
Following are the my.cnf files:
On slave:
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
# Recommended in standard MySQL setup
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
server-id=2
log-bin=mysql-bin
binlog_format=ROW
relay_log=relay-log
skip-slave-start
enforce-gtid-consistency
gtid-mode=ON
log-slave-updates
[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
On mater:
[mysqld]
server-id=1
log-bin=mysql-bin
binlog_format=ROW
gtid-mode=on
enforce-gtid-consistency
log-slave-updates
innodb_buffer_pool_size = 1G
query_cache_size = 32M
Slave machine: Centos 6.6, mysql 5.6.24.
Master machine: RHEL 6.6, mysql 5.6.10.
Any help wold be greatly appreciated!
Thanks
Nadav Blum
on master -
mysql> reset master;
[this command will clear binary logs of master and start with new. so save it if you want.]
when you start the slave mysqld, run the following command
mysql> stop salve;
mysql> reset slave;
mysql> change master to master_host='192.168.10.116', master_user='root', master_password='root', master_auto_position=1;
mysql> start slave;
mysql> show slave status \G
Now if all goes well then, you can restart the slave (if it is committed all the transaction then no problem else it will start to execute transection in your master binary log. You can check your relay log file)
Well, mystery solved.
Remember how I wrote that the issue has nothing to do with my usage of stunnel, as the mean for tunneling communication between master and slave ?
Well, I was wrong.
The thing is, I used localhost port 3307 as the end point for the slave communication to the master. (stunnel listened to this port and forwarded data to the master-server ip). So the "change master" was done via:
change master to master_host="localhost", master_port=3307, master_user="XXX", master_password="XXX", MASTER_AUTO_POSITION = 1;'
That "localhost" thing caused the mess. I changed it to "127.0.0.1", and now restarts cause no harm!
Thanks Hitech and Jaydee for your help!
Ran into the same problem yesterday.
Oracle support doc helped.
For people who don't have Oracle support.
CAUSE
The cause is that both TABLE and FILE replication repository metadata exist at the same time, but only one form should.
SOLUTION
Before setting up replication, remove the files specified by the my.cnf variables relay_log_info_file and master_info_file .
By default their names map to relay-log.info and master.info and they are located in the datadir. (I had to remove the master.info file)
And remove any residual configuration by executing:
STOP SLAVE;
SET SQL_LOG_BIN=0;
DELETE FROM mysql.slave_master_info ;
DELETE FROM mysql.slave_relay_log_info ;
SET SQL_LOG_BIN=1;

MySQL binary logs will not start

In-Short: My binary logs aren't starting even though log-bin is set and specified. I'm not sure how to fix it.
I have a MariaDB instance running as a service on windows that I am attempting to replicate to a MariaDB instance on a Ubuntu machine. I am using MySQL workbench 6.0 as much as I can to manage everything, and following the instructions from Oracle here for setting up master-slave replication: http://dev.mysql.com/doc/refman/5.0/en/replication-howto.html
I have made it to the fourth chapter, where I allegedly have the master and slave both configured, and I am about to read-lock the master tables for an initial data dump to the slave before I start up replication. So I flushed the tables with read lock and checked the master status:
FLUSH TABLES WITH READ LOCK;
SHOW MASTER STATUS;
That last line didn't return any binary log information. Checking further, I ran:
SHOW BINARY LOGS;
and an error message confirmed that:
Error Code: 1381. You are not using binary logging
Master Config is like this:
[mysqld]
datadir = "C:/mysql/data"
port=3306
sql_mode="STRICT_TRANS_TABLES,NO_ENGINE_SUBSTITUTION"
default_storage_engine=innodb
innodb_buffer_pool_size=1535M
innodb_log_file_size=50M
feedback=ON
innodb_flush_log_at_trx_commit = 1
sync_binlog = 1
log-bin-index = "C:/mysql/logs/log-bin.index"
log-bin=mysql-bin
server-id=1
innodb_flush_log_at_trx_commit=1
[client]
port=3306
How do I make sure the binary logs are rolling so I can continue with this?

Binary log error in mysql

When I am trying to check binary log:
SHOW BINARY LOGS;
I get this error:
ERROR 1381 (HY000): You are not using binary logging.
How to resolve this? Can anybody help?
Set the log-bin variable in your MySQL configuration file, then restart MySQL.
An example my.cnf (on Linux/unix) or my.ini (on Windows) would look like:
[client]
...
[mysqld]
...
log-bin=mysql-bin
---
Once restarted, MySQL automatically creates a new binary log (does so upon every restart).
You may also wish to look at the following variables:
server-id = 1
expire_logs_days = 4
sync_binlog = 1
Read details on the MySQL documentation. If you're after replication setup (a primary reason for using binary logs), check out Replication configuration checklist.
Line
log-bin=mysql-bin
must placed above lines:
[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
You will need to activate binary logging at startup
Add the following lines in /etc/my.cnf under the [mysqld] section
[mysqld]
log-bin=mysql-bin
expire-logs-days=7
Then, run this
service mysql restart
The next time you login to mysql, you will see a binary log listing and will rotate out after 7 days.
The default location of the binary logs will be /var/lib/mysql or where datadir is defined. If you specify a folder before the binlog name, then that folder is the location.
For example
[mysqld]
log-bin=/var/log/mysql-bin
expire-logs-days=7
UPDATE 2012-07-12 02:20 AM EDT
Please restart mysql as follows and tell us if binary logging in on
service mysql restart --log-bin=mysql-bin
To enable the binary log, start the server with the --log-bin[=base_name] option.
If no base_name value is given, the default name is the value of the pid-file option (which by default is the name of host machine) followed by -bin.
If the basename is given, the server writes the file in the data directory unless the basename is given with a leading absolute path name to specify a different directory. It is recommended that you specify a basename.
Or you can directly use:
log-bin=mysql-bin
and then restart your mysql service. Then binary file will be generated. If you are using lampp on Linux machine then you will find this file in /lampp/var/mysql/mysql-bin.000001
FWIW, I had the same issue after I tried to set up my.cnf.master and my.cnf.slave files and symlink them to my.cnf for master and slave, respectively. The idea was to be able to switch the machine from master to slave and back easily.
It turned out that mysqld simply did not handle the symlink as expected. Hard-linking the file worked (ln my.cnf.master my.cnf). Careful if you do something like this, as overwriting one of the hard-linked filenames could break the link and create two separate files instead (depending on the method of rewriting employed by the software you use for it).
I've found logging will silently fail to happen even if my.cnf config is right, so you can also try re-creating your log folder.
This may be necwssary if the logs are in an odd state. (In my case, I had simply ceased logging in my.cnf and then re-enabled it, but nothing happened, probably because the existing files were not the latest updates?).
Something like this should work:
sudo service mysql stop
sudo mv /var/log/mysql /tmp/mysqlold # or rm -fr if you're brave
mkdir /var/log/mysql
chown -R mysql:mysql /var/log/mysql
sudo service mysql start
Obligatory warning: Obviously, take care when deleting anything on a database server. This will destroy/disrupt/corrupt any replication using this database as master (though you can resume replication as a slave). That said, I believe this should be safe insofar as it doesn't delete the database itself.
I went out of my mind with this issue on a MySQL 5.5 master running Debian. None of the above worked. Finally, I rebooted the server and logging was enabled.
Remove section [mysqld_safe] and replace with [mysqld].
It works for me.