2017-10-13

zabbix进行数据库备份以及表分区

由于测试环境上面使用的zabbix服务器配置比较低，经常会遇到性能瓶颈（主要是数据库和磁盘I/O等），于是倒逼我使用了一些方式来缓解这些问题。

主要是以前使用的那个备份数据库的脚本是对zabbix数据库进行全备的，使用的又是mysql自带的工具mysqldump，当数据量大了之后进行全备所花的时间比较长，这样将会造成数据库的锁读。。。从而使zabbix服务以为mysql死掉了，产生一大堆的报警。

后来发现原来造成数据库数据量大量增加的是zabbix数据库中的一些存储数据的大表导致的。于是备份数据库的时候可以选择跳过这些表进行备份，这样，将大大减少数据库备份所花的时间（PS：之前备份数据库所花时间在十分钟左右，现在跳过大表备份，所花时间在1S左右就能备份完，大大缩短了备份数据库时间）。

下面就贴出某位大神写的专门为zabbix数据库做备份以及恢复的脚本：

#!/bin/bash
#author: itnihao
red='\e[0;31m' # 红色 
RED='\e[1;31m' 
green='\e[0;32m' # 绿色 
GREEN='\e[1;32m' 
blue='\e[0;34m' # 蓝色 
BLUE='\e[1;34m' 
purple='\e[0;35m' # 紫色 
PURPLE='\e[1;35m' 
NC='\e[0m' # 没有颜色 
source /etc/bashrc
source /etc/profile
MySQL_USER=zabbix
MySQL_PASSWORD=zabbix
MySQL_HOST=localhost
MySQL_PORT=3306
MySQL_DUMP_PATH=/opt/backup
MYSQL_BIN_PATH=/opt/software/mysql/bin/mysql
MYSQL_DUMP_BIN_PATH=/opt/software/mysql/bin/mysqldump
MySQL_DATABASE_NAME=zabbix
DATE=$(date '+%Y%m%d')
MySQLDUMP () {
 [ -d ${MySQL_DUMP_PATH} ] || mkdir ${MySQL_DUMP_PATH}
 cd ${MySQL_DUMP_PATH}
 [ -d logs ] || mkdir logs
 [ -d ${DATE} ] || mkdir ${DATE}
 cd ${DATE}
  
 #TABLE_NAME_ALL=$(${MYSQL_BIN_PATH} -u${MySQL_USER} -p${MySQL_PASSWORD} -h${MySQL_HOST} ${MySQL_DATABASE_NAME} -e "show tables"|egrep -v "(Tables_in_zabbix)")
 TABLE_NAME_ALL=$(${MYSQL_BIN_PATH} -u${MySQL_USER} -p${MySQL_PASSWORD} -h${MySQL_HOST} ${MySQL_DATABASE_NAME} -e "show tables"|egrep -v "(Tables_in_zabbix|history*|trends*|acknowledges|alerts|auditlog|events|service_alarms)")
 for TABLE_NAME in ${TABLE_NAME_ALL}
 do
 ${MYSQL_DUMP_BIN_PATH} --opt -u${MySQL_USER} -p${MySQL_PASSWORD} -P${MySQL_PORT} -h${MySQL_HOST} ${MySQL_DATABASE_NAME} ${TABLE_NAME} >${TABLE_NAME}.sql
 sleep 0.01
 done
 [ "$?" == 0 ] && echo "${DATE}: Backup zabbix succeed" >> ${MySQL_DUMP_PATH}/logs/ZabbixMysqlDump.log
 [ "$?" != 0 ] && echo "${DATE}: Backup zabbix not succeed" >> ${MySQL_DUMP_PATH}/logs/ZabbixMysqlDump.log
  
 cd ${MySQL_DUMP_PATH}/
 rm -rf $(date +%Y%m%d --date='5 days ago')
 exit 0
}
MySQLImport () {
 cd ${MySQL_DUMP_PATH}
 DATE=$(ls ${MySQL_DUMP_PATH} |egrep "\b^[0-9]+$\b")
 echo -e "${green}${DATE}"
 echo -e "${blue}what DATE do you want to import,please input date:${NC}"
 read SELECT_DATE
 if [ -d "${SELECT_DATE}" ];then
 echo -e "you select is ${green}${SELECT_DATE}${NC}, do you want to contine,if,input ${red}(yes|y|Y)${NC},else then exit"
 read Input
 [[ 'yes|y|Y' =~ "${Input}" ]]
 status="$?"
 if [ "${status}" == "0" ];then
 echo "now import SQL....... Please wait......."
 else
 exit 1
 fi
 cd ${SELECT_DATE}
 for PER_TABEL_SQL in $(ls *.sql)
 do
 ${MYSQL_BIN_PATH} -u${MySQL_USER} -p${MySQL_PASSWORD} -h${MySQL_HOST} ${MySQL_DATABASE_NAME} < ${PER_TABEL_SQL}
 echo -e "import ${PER_TABEL_SQL} ${PURPLE}........................${NC}"
 done 
 echo "Finish import SQL,Please check Zabbix database"
 else 
 echo "Don't exist ${SELECT_DATE} DIR" 
 fi
}
case "$1" in
MySQLDUMP|mysqldump)
 MySQLDUMP
 ;;
MySQLImport|mysqlimport)
 MySQLImport
 ;;
*)
 echo "Usage: $0 {(MySQLDUMP|mysqldump) (MySQLImport|mysqlimport)}"
 ;;
esac

该脚本源出处在这https://github.com/itnihao/zabbix-book/blob/master/03-chapter/Zabbix_MySQLdump_per_table_v2.sh

这是在大神的脚本上做了修改之后形成的适合我自己备份的脚本，各位也可以自行修改成适合自己的备份脚本。这个脚本实现的效果上面已经说了，之前做全备的时候差不多有4G左右的数据量，现在只备份配置文件数据量只有不到10M，果断大大节省时间以及空间呀。

不过这样的话将无法保证数据的备份，目前考虑使用xtradbbackup对数据进行增量备份，目前还未实现，留待过两天做吧。

好了，关于数据库备份的事情搞了，然后还需要对大数据量的表进行表分区，参考了zabbix官网的一篇文章https://www.zabbix.org/wiki/Docs/howto/mysql_partition 各位有兴趣的话可以去看看，我这里将其总结在了一起，更加方便一点。

表分区可以对大数据量的表进行物理上的拆分成多个文件，但是逻辑上来看，还是一张表，对应用程序是透明的。另外，将这一张大表拆分成很多小表的话将使得数据查询速度能够更快。还可以随时删除旧的数据分区，删除过期数据。这种方式适用于大数据量的表，但是查询量比较少的应用场景。如果是大数据量的表，又有大量查询的话建议还是进行分库分表操作。

首先，登录数据库(PS:这个就不演示了)

然后登陆到zabbix库中修改两张表的结构：

1
2
3

use zabbix;
Alter table history_text drop primary key, add index (id), drop index history_text_2, add index history_text_2 (itemid, id);
Alter table history_log drop primary key, add index (id), drop index history_log_2, add index history_log_2 (itemid, id);

修改完之后再按照官网上的过程创建四个存储过程：

DELIMITER $$
CREATE PROCEDURE `partition_create`(SCHEMANAME VARCHAR(64), TABLENAME VARCHAR(64), PARTITIONNAME VARCHAR(64), CLOCK INT)
BEGIN
 /*
 SCHEMANAME = The DB schema in which to make changes
 TABLENAME = The table with partitions to potentially delete
 PARTITIONNAME = The name of the partition to create
 */
 /*
 Verify that the partition does not already exist
 */
  
 DECLARE RETROWS INT;
 SELECT COUNT(1) INTO RETROWS
 FROM information_schema.partitions
 WHERE table_schema = SCHEMANAME AND TABLE_NAME = TABLENAME AND partition_description >= CLOCK;
  
 IF RETROWS = 0 THEN
 /*
 1. Print a message indicating that a partition was created.
 2. Create the SQL to create the partition.
 3. Execute the SQL from #2.
 */
 SELECT CONCAT( "partition_create(", SCHEMANAME, ",", TABLENAME, ",", PARTITIONNAME, ",", CLOCK, ")" ) AS msg;
 SET @SQL = CONCAT( 'ALTER TABLE ', SCHEMANAME, '.', TABLENAME, ' ADD PARTITION (PARTITION ', PARTITIONNAME, ' VALUES LESS THAN (', CLOCK, '));' );
 PREPARE STMT FROM @SQL;
 EXECUTE STMT;
 DEALLOCATE PREPARE STMT;
 END IF;
END
$$DELIMITER ;

DELIMITER $$
CREATE PROCEDURE `partition_drop`(SCHEMANAME VARCHAR(64), TABLENAME VARCHAR(64), DELETE_BELOW_PARTITION_DATE BIGINT)
BEGIN
 /*
 SCHEMANAME = The DB schema in which to make changes
 TABLENAME = The table with partitions to potentially delete
 DELETE_BELOW_PARTITION_DATE = Delete any partitions with names that are dates older than this one (yyyy-mm-dd)
 */
 DECLARE done INT DEFAULT FALSE;
 DECLARE drop_part_name VARCHAR(16);
  
 /*
 Get a list of all the partitions that are older than the date
 in DELETE_BELOW_PARTITION_DATE. All partitions are prefixed with
 a "p", so use SUBSTRING TO get rid of that character.
 */
 DECLARE myCursor CURSOR FOR
 SELECT partition_name
 FROM information_schema.partitions
 WHERE table_schema = SCHEMANAME AND TABLE_NAME = TABLENAME AND CAST(SUBSTRING(partition_name FROM 2) AS UNSIGNED) < DELETE_BELOW_PARTITION_DATE;
 DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
  
 /*
 Create the basics for when we need to drop the partition. Also, create
 @drop_partitions to hold a comma-delimited list of all partitions that
 should be deleted.
 */
 SET @alter_header = CONCAT("ALTER TABLE ", SCHEMANAME, ".", TABLENAME, " DROP PARTITION ");
 SET @drop_partitions = "";
  
 /*
 Start looping through all the partitions that are too old.
 */
 OPEN myCursor;
 read_loop: LOOP
 FETCH myCursor INTO drop_part_name;
 IF done THEN
 LEAVE read_loop;
 END IF;
 SET @drop_partitions = IF(@drop_partitions = "", drop_part_name, CONCAT(@drop_partitions, ",", drop_part_name));
 END LOOP;
 IF @drop_partitions != "" THEN
 /*
 1. Build the SQL to drop all the necessary partitions.
 2. Run the SQL to drop the partitions.
 3. Print out the table partitions that were deleted.
 */
 SET @full_sql = CONCAT(@alter_header, @drop_partitions, ";");
 PREPARE STMT FROM @full_sql;
 EXECUTE STMT;
 DEALLOCATE PREPARE STMT;
  
 SELECT CONCAT(SCHEMANAME, ".", TABLENAME) AS `table`, @drop_partitions AS `partitions_deleted`;
 ELSE
 /*
 No partitions are being deleted, so print out "N/A" (Not applicable) to indicate
 that no changes were made.
 */
 SELECT CONCAT(SCHEMANAME, ".", TABLENAME) AS `table`, "N/A" AS `partitions_deleted`;
 END IF;
END$$
DELIMITER ;

DELIMITER $$
CREATE PROCEDURE `partition_maintenance`(SCHEMA_NAME VARCHAR(32), TABLE_NAME VARCHAR(32), KEEP_DATA_DAYS INT, HOURLY_INTERVAL INT, CREATE_NEXT_INTERVALS INT)
BEGIN
 DECLARE OLDER_THAN_PARTITION_DATE VARCHAR(16);
 DECLARE PARTITION_NAME VARCHAR(16);
 DECLARE LESS_THAN_TIMESTAMP INT;
 DECLARE CUR_TIME INT;
  
 CALL partition_verify(SCHEMA_NAME, TABLE_NAME, HOURLY_INTERVAL);
 SET CUR_TIME = UNIX_TIMESTAMP(DATE_FORMAT(NOW(), '%Y-%m-%d 00:00:00'));
  
 SET @__interval = 1;
 create_loop: LOOP
 IF @__interval > CREATE_NEXT_INTERVALS THEN
 LEAVE create_loop;
 END IF;
  
 SET LESS_THAN_TIMESTAMP = CUR_TIME + (HOURLY_INTERVAL * @__interval * 3600);
 SET PARTITION_NAME = FROM_UNIXTIME(CUR_TIME + HOURLY_INTERVAL * (@__interval - 1) * 3600, 'p%Y%m%d%H00');
 CALL partition_create(SCHEMA_NAME, TABLE_NAME, PARTITION_NAME, LESS_THAN_TIMESTAMP);
 SET @__interval=@__interval+1;
 END LOOP;
  
 SET OLDER_THAN_PARTITION_DATE=DATE_FORMAT(DATE_SUB(NOW(), INTERVAL KEEP_DATA_DAYS DAY), '%Y%m%d0000');
 CALL partition_drop(SCHEMA_NAME, TABLE_NAME, OLDER_THAN_PARTITION_DATE);
  
END$$
DELIMITER ;

DELIMITER $$
CREATE PROCEDURE `partition_verify`(SCHEMANAME VARCHAR(64), TABLENAME VARCHAR(64), HOURLYINTERVAL INT(11))
BEGIN
 DECLARE PARTITION_NAME VARCHAR(16);
 DECLARE RETROWS INT(11);
 DECLARE FUTURE_TIMESTAMP TIMESTAMP;
  
 /*
 * Check if any partitions exist for the given SCHEMANAME.TABLENAME.
 */
 SELECT COUNT(1) INTO RETROWS
 FROM information_schema.partitions
 WHERE table_schema = SCHEMANAME AND TABLE_NAME = TABLENAME AND partition_name IS NULL;
  
 /*
 * If partitions do not exist, go ahead and partition the table
 */
 IF RETROWS = 1 THEN
 /*
 * Take the current date at 00:00:00 and add HOURLYINTERVAL to it. This is the timestamp below which we will store values.
 * We begin partitioning based on the beginning of a day. This is because we don't want to generate a random partition
 * that won't necessarily fall in line with the desired partition naming (ie: if the hour interval is 24 hours, we could
 * end up creating a partition now named "p201403270600" when all other partitions will be like "p201403280000").
 */
 SET FUTURE_TIMESTAMP = TIMESTAMPADD(HOUR, HOURLYINTERVAL, CONCAT(CURDATE(), " ", '00:00:00'));
 SET PARTITION_NAME = DATE_FORMAT(CURDATE(), 'p%Y%m%d%H00');
  
 -- Create the partitioning query
 SET @__PARTITION_SQL = CONCAT("ALTER TABLE ", SCHEMANAME, ".", TABLENAME, " PARTITION BY RANGE(`clock`)");
 SET @__PARTITION_SQL = CONCAT(@__PARTITION_SQL, "(PARTITION ", PARTITION_NAME, " VALUES LESS THAN (", UNIX_TIMESTAMP(FUTURE_TIMESTAMP), "));");
  
 -- Run the partitioning query
 PREPARE STMT FROM @__PARTITION_SQL;
 EXECUTE STMT;
 DEALLOCATE PREPARE STMT;
 END IF;
END$$
DELIMITER ;

上面四个存储过程执行后将可以使用

1	CALL partition_maintenance('<zabbix_db_name>', '<table_name>', <days_to_keep_data>, <hourly_interval>, <num_future_intervals_to_create>)

命令对想要分区的表进行表分区了。其中的参数我这里解释一下。

这是举例：

1	CALL partition_maintenance(zabbix, 'history_uint', 31, 24, 14);

zabbix_db_name：库名
table_name：表名
days_to_keep_data：保存多少天的数据
hourly_interval：每隔多久生成一个分区
num_future_intervals_to_create：本次一共生成多少个分区

这个例子就是history_uint表最多保存31天的数据，每隔24小时生成一个分区，这次一共生成14个分区
这里可以将上面四个存储过程保存为一个文件，导入到数据库中，文件我稍后将会放在附件中，这里使用的命令是：

1	mysql -uzabbix -pzabbix zabbix<partition_call.sql

然后可以将CALL统一调用也做成一个文件，统一调用的内容如下：

DELIMITER $$
CREATE PROCEDURE `partition_maintenance_all`(SCHEMA_NAME VARCHAR(32))
BEGIN
 CALL partition_maintenance(SCHEMA_NAME, 'history', 31, 24, 14);
 CALL partition_maintenance(SCHEMA_NAME, 'history_log', 31, 24, 14);
 CALL partition_maintenance(SCHEMA_NAME, 'history_str', 31, 24, 14);
 CALL partition_maintenance(SCHEMA_NAME, 'history_text', 31, 24, 14);
 CALL partition_maintenance(SCHEMA_NAME, 'history_uint', 31, 24, 14);
 CALL partition_maintenance(SCHEMA_NAME, 'trends', 180, 24, 14);
 CALL partition_maintenance(SCHEMA_NAME, 'trends_uint', 180, 24, 14);
END$$
DELIMITER ;

也将该文件导入到数据库中，使用命令：

1	mysql -uzabbix -pzabbix zabbix<partition_all.sql

好了，到了这里之后就可以使用如下命令执行表分区了：

mysql -uzabbix -pzabbix zabbix -e "CALL partition_maintenance_all('zabbix');"
+----------------+--------------------+
| table | partitions_deleted |
+----------------+--------------------+
| zabbix.history | N/A |
+----------------+--------------------+
+--------------------+--------------------+
| table | partitions_deleted |
+--------------------+--------------------+
| zabbix.history_log | N/A |
+--------------------+--------------------+
+--------------------+--------------------+
| table | partitions_deleted |
+--------------------+--------------------+
| zabbix.history_str | N/A |
+--------------------+--------------------+
+---------------------+--------------------+
| table | partitions_deleted |
+---------------------+--------------------+
| zabbix.history_text | N/A |
+---------------------+--------------------+
+---------------------+--------------------+
| table | partitions_deleted |
+---------------------+--------------------+
| zabbix.history_uint | N/A |
+---------------------+--------------------+
+---------------+--------------------+
| table | partitions_deleted |
+---------------+--------------------+
| zabbix.trends | N/A |
+---------------+--------------------+
+--------------------+--------------------+
| table | partitions_deleted |
+--------------------+--------------------+
| zabbix.trends_uint | N/A |
+--------------------+--------------------+

看到如下结果证明所有7张表都进行了表分区，也可以在Mysql的数data目录下看到新生成的表分区文件。（PS:注意，最好是清空history_uint表的数据之后再执行上面这条命令，否则因为这张表数据量太大，转换时间将会好长，清空表中数据的命令为： truncate table history_uint;）

好了，这样可以进行表分区了。

将上面这条命令写入到计划任务中如下：

1 2	crontab -l\|tail -1 01 01 * * * /opt/software/mysql/bin/mysql -uzabbix -pzabbix zabbix -e "CALL partition_maintenance_all('zabbix');"

每天晚上的1点01执行一次。还有之前写的备份数据库的脚本也需要执行计划任务每天的凌晨0点01执行备份：

1 2	crontab -l\|tail -2\|head -1 01 00 * * * /usr/local/scripts/Zabbix_MySQLdump_per_table_v2.sh mysqldump

这样就大功告成了，之后再体验一下zabbix的web页面看是不是感觉比以前快了？