Why does Master think it's a Slave on Reboot?

Question

In a simple MySQL replication Master-Slave configuration I have a problem where Master tries to connect to itself as a slave on reboot.

So when I restart MySQL on Master, I see errors related to the same server trying to replicate to itself and I have to manually run mysql -e "STOP SLAVE;" every time I restart MySQL.

How can I disable slave on master for good?

Here's the relevant portion of my.cnf:

## Logging
binlog_format                   = mixed
log_bin                         = /var/log/mysql/mysql-bin.log
sync_binlog                     = 1
pid_file                        = /var/run/mysqld/mysqld.pid
log_error                       = /var/log/mysql/error.log
#general_log                     = 0
#general_log_file                = /var/log/mysql/general.log
slow_query_log                  = 1
slow_query_log_file             = /var/log/mysql/slow.log
long_query_time                 = 3
expire_logs_days                = 14

sql_mode                        = STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
# sql_mode                        = ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION

## Replication
server_id                       = 200

## Master Configuration
binlog-do-db                    = my_db_1
binlog-do-db                    = my_db_2
binlog-do-db                    = my_db_3
binlog-do-db                    = my_db_4
binlog-do-db                    = my_db_5
binlog-do-db                    = my_db_6

Also, when I run SELECT * FROM mysql.user; I don't see the repl user that's allegedly a "slave" on Master.

BUT, I do see that localhost has replication grants:

mysql> select Host, User, grant_priv, Repl_slave_priv, Repl_client_priv from mysql.user;
+-----------------+---------------+------------+-----------------+------------------+
| Host            | User          | grant_priv | Repl_slave_priv | Repl_client_priv |
+-----------------+---------------+------------+-----------------+------------------+
| localhost       | root          | Y          | Y               | Y                |
| localhost       | mysql.sys     | N          | N               | N                |

Here's an example of the errors I see on Reboot (before I run STOP SLAVE; on Master):

2016-09-01T15:22:23.845505Z 384 [Note] Access denied for user 'repl'@'192.168.100.200' (using password: YES)
2016-09-01T15:22:23.845761Z 1 [ERROR] Slave I/O for channel '': error connecting to master '[email protected]:3306' - retry-time: 30  retries: 8, Error_code: 1045
2016-09-01T15:22:50.191636Z 0 [Note] InnoDB: page_cleaner: 1000ms intended loop took 6843ms. The settings might not be optimal. (flushed=15210 and evicted=0, during the time.)

Apart from this, replication is running fine. Writes to Master show up flawlessly on the real, read-only, Slave.

---

Full my.cnf:

[mysql]
default_character_set           = utf8

[mysqld]
datadir                         = /var/lib/mysql
socket                          = /var/lib/mysql/mysql.sock

symbolic-links                  = 0

## Custom Configuration
skip_external_locking           = 1
skip_name_resolve
open_files_limit                = 20000

## Cache
thread_cache_size               = 16
query_cache_type                = 1
query_cache_size                = 256M
query_cache_limit               = 4M

## Per-thread Buffers
sort_buffer_size                = 32M
read_buffer_size                = 4M
read_rnd_buffer_size            = 8M
join_buffer_size                = 2M

## Temp Tables
tmp_table_size                  = 1024M
max_heap_table_size             = 1024M

## Networking
back_log                        = 250
max_connections                 = 512
max_connect_errors              = 100000
max_allowed_packet              = 128M
interactive_timeout             = 1800
wait_timeout                    = 1800
character_set_client_handshake  = FALSE
character_set_server            = utf8mb4
collation_server                = utf8mb4_unicode_ci

### Storage Engines
default_storage_engine          = InnoDB
innodb                          = FORCE

## MyISAM
key_buffer_size                 = 128M
myisam_sort_buffer_size         = 16M

## InnoDB
innodb_buffer_pool_size         = 46G
innodb_buffer_pool_instances    = 64
innodb_log_files_in_group       = 2
innodb_log_buffer_size          = 32M
innodb_log_file_size            = 64M
innodb_file_per_table           = 1
innodb_thread_concurrency       = 0
innodb_flush_log_at_trx_commit  = 1

## Logging
binlog_format                   = mixed
log_bin                         = /var/log/mysql/mysql-bin.log
sync_binlog                     = 1
pid_file                        = /var/run/mysqld/mysqld.pid
log_error                       = /var/log/mysql/error.log
#general_log                     = 0
#general_log_file                = /var/log/mysql/general.log
slow_query_log                  = 1
slow_query_log_file             = /var/log/mysql/slow.log
long_query_time                 = 3
expire_logs_days                = 14

sql_mode                        = STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
# sql_mode                        = ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION

## Replication
# Master Server ID:
server_id                       = 200
# Slave Server ID:
# server_id                       = 300

## Master Configuration
# Comment out on Slave
binlog-do-db                    = db_1
binlog-do-db                    = db_2
binlog-do-db                    = db_3
binlog-do-db                    = db_4
binlog-do-db                    = db_5
binlog-do-db                    = db_6

## Slave Configuration
# Uncomment the following on Slave
# relay-log                       = /var/log/mysql/mysql-relay-bin.log
# binlog-do-db                    = db_1
# binlog-do-db                    = db_2
# binlog-do-db                    = db_3
# binlog-do-db                    = db_4
# binlog-do-db                    = db_5
# binlog-do-db                    = db_6
# log_slave_updates               = 1
# read_only                       = 1
# slave_skip_errors               = 1062

[mysqld_safe]
datadir                         = /var/lib/mysql
socket                          = /var/lib/mysql/mysql.sock
symbolic-links                  = 0
pid_file                        = /var/run/mysqld/mysqld.pid
log_error                       = /var/log/mysql/error.log

Also:

mysql> SHOW GLOBAL VARIABLES LIKE '%master_info_repository%';
+------------------------+-------+
| Variable_name          | Value |
+------------------------+-------+
| master_info_repository | FILE  |
+------------------------+-------+

Answer 1

For managing this kind of setups I recommend to use MHA manager. For this specific situation you may want to clean up the master_info_repository (located by default in master.info). Also, you can use --skip-slave-start on the master host to avoid this situations after failover.