MySQL databases are located on /var/lib/mysql, if you create a partition for /var and and big enough to hold your databases MySQL will stop working because not enough space to put the data. Below is the easy way to fix it:
(more…)
I was checking Development MySQL server (what did you know, I am not that lazy) and I found errors at /var/log/messages, I assume the secondary HDD (/dev/hdb) failed. Fiuh, I am lucky configured this server using Software-Raid1 otherwise all data has gone.
Jun 19 15:51:56 dbdemo smartd[2117]: Device: /dev/hdb, 37997 Currently unreadable (pending) sectors
Jun 19 15:51:56 dbdemo smartd[2117]: Device: /dev/hdb, 37997 Offline uncorrectable sectors
Jun 19 16:21:57 dbdemo smartd[2117]: Device: /dev/hdb, 38010 Currently unreadable (pending) sectors
Jun 19 16:21:57 dbdemo smartd[2117]: Device: /dev/hdb, 38010 Offline uncorrectable sectors
Jun 19 16:23:47 dbdemo kernel: hdb: task_in_intr: status=0x59 { DriveReady SeekComplete DataRequest Error }
Luckily, uncle Google very nice to me and show me article on Howtoforge.com, following the article I am confident to replace failed harddisk. Below is my Raid configuration:
Array: /dev/md0; Member: /dev/hda1 /dev/hdb1; Raid: 1; Filesystem: ext3fs; mountpoint: /boot
Array: /dev/md1; Member: /dev/hda2 /dev/hdb2; Raid: 0; Filesystem: swap; mountpoint: swap
Array: /dev/md2; Member: /dev/hda3 /dev/hdb3; Raid: 1; Filesystem: ext3fs; mountpoint: /
Summary of Howtoforge’s article is below:
Today I upgraded my HeidiSQL into version 4, but when I am running it on the MySQL server 5.0 I got error
"SQL Error: Table 'mysql.proc' doesn't exist"
After googling around, found that this error caused HeidiSQL requires table Mysql.proc which is not exist. Table Mysql.proc is used to store procedure. But wait, I am using MySQL 5.0.x which already support Procedures and Views!! so How come this error show up??
After some tought, the are several reason why this error came up although you are using MySQL 5.
And in my case, it was reason no. 1, as I am remember I was once upgrade mysql server a year ago. So how to fix it? (more…)
Since I sometimes get replication problem, so I make several script to check replication automatically and report to me:
To check replication status when I in the console and playing with replication configuration or when I have nothing to do yet I want to see a black screen 
monitorreplication.sh
#!/bin/bash
while [ 1 ]
do
# Your code goes here
echo ""
date
echo "=============================="
mysql -u backup -pmysqlback -e "show slave status\G;"
# Modify sleep time (in seconds) as needed below
sleep 10
done
Another scripts to send replication status via email
(more…)
Okay it’s the second time this problem arise, so I’ll put a blog here just incase it happen again in near future. The replication on slave server just stop working with error
Could not parse relay log event entry. The possible reasons are: the master’s binary log is corrupted (you can check this by running ‘mysqlbinlog’ on the binary log), the slave’s relay log is corrupted (you can check this by running ‘mysqlbinlog’ on the relay log), a network problem, or a bug in the master’s or slave’s MySQL code. If you want to check the master’s binary log or slave’s relay log, you will be able to know their names by issuing ‘SHOW SLAVE STATUS’ on this slave.
Googling up and check several paramters:
on master server:
mysql> show master status\G; *************************** 1. row *************************** File: replication.011 Position: 130848689 Binlog_do_db: Binlog_ignore_db: 1 row in set (0.00 sec)
on slave server:
mysql> show slave status\G; *************************** 1. row *************************** Master_Host: 10.10.105.11 Master_User: repl Master_Port: 3306 Connect_retry: 60 Master_Log_File: replication.011 Read_Master_Log_Pos: 91831752 Relay_Log_File: dragon-relay-bin.183 Relay_Log_Pos: 3551175 Relay_Master_Log_File: replication.011 Slave_IO_Running: No Slave_SQL_Running: No Replicate_do_db: Replicate_ignore_db: Last_errno: 0 Last_error: Could not parse relay log event entry. The possible reasons are: the master's binary log is corrupted (you can check this by running 'mysqlbinlog' on the binary log), the slave's relay log is corrupted (you can check this by running 'mysqlbinlog' on the relay log), a network problem, or a bug in the master's or slave's MySQL code. If you want to check the master's binary log or slave's relay log, you will be able to know their names by issuing 'SHOW SLAVE STATUS' on this slave. Skip_counter: 0 Exec_master_log_pos: 74359528 Relay_log_space: 21023399 [root@dragon mysql]# tail -f dragon.rpxholding.com.err 081129 0:54:24 Error in Log_event::read_log_event(): 'read error', data_len: 148, event_type: 2 081129 0:54:24 Error reading relay log event: slave SQL thread aborted because of I/O error 081129 0:54:24 Slave: Could not parse relay log event entry. The possible reasons are: the master's binary log is corrupted (you can check this by running 'mysqlbinlog' on the binary log), the slave's relay log is corrupted (you can check this by running 'mysqlbinlog' on the relay log), a network problem, or a bug in the master's or slave's MySQL code. If you want to check the master's binary log or slave's relay log, you will be able to know their names by issuing 'SHOW SLAVE STATUS' on this slave. Error_code: 0
Slave IO and SQL are not running. What caused the problem ? binlog file at master is not corrupted. That’s great and very good news. But relay log file at slave is corrupted. That’s what make replication can’t read it. Fixing the problem: