Redis master-slave replication for building high-performance database caches

First,What isRedismaster-slave replication?

master-slave replication, when users go to When the Master side writes data, the data file is sent to Slave via the Redis Sync mechanism,and Slave performs the same operation to ensure the data is consistent; The master-slave replication is very simple.

Second,Redismaster-slave replication features

1, the same Master can have more than one slaves.

2,Master under the Slave can also accept the same schema other Slave link and synchronization requests, to achieve cascade replication of data, that is master->slave-> Slave mode;

3. Master synchronizes data to slave in a non-blocking manner , which will mean that master will continue to process one or more slave read and write requests;

4,Slave -side synchronization data can also be modified to non-blocking is the way, when the Slave in performing a new synchronization, it can still use the old data information to provide queries; otherwise, when Slave and when Master loses contact,slave returns an error to the client;

5, master-slave replication has scalability, that is, multiple slave dedicated to provide read-only query and data redundancy,Master dedicated to provide write operations;

6, through the configuration disables the master data persistence mechanism, the data persistence operation to the slaves completes, avoids in the master to have the independent process to complete this operation.

Third,RedisMaster-slave replication principle

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Iv. List of server resources

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Five, the configuration process

about the Redis Installation and configuration It's not working here. READ: Redis for high performance Database Cache (i)http://cfwlxf.blog.51cto.com/3966339/1423106

3,1 MasterThe end operation is as follows:RunRedisService

[Email protected]_master sh]# redis-server/etc/redis/redis.conf

EnquiryRedisRun Log

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## by reading some of the information in the log file output, you can see Master with the Slave session mechanism to be performed when a connection is established: Load the data file to the hard disk, when 0.012 seconds, imagine the speed is how fast, of course, according to the size of the data to evaluate; services connected to 6379 Port, received Slave Sync connection request, open "BGSAVE" synchronization, etc.;

ClearMasterin the End database, allKey

[[Email protected]_master sh]# redis-cli127.0.0.1:6379> flushallok127.0.0.1:6379> keys * (empty list or set)

3,2 SlaveThe end operation is as follows:

[Email protected]_slave ~]# vim/etc/redis/redis.conf

# Add the IP and Port on the Master side

# slaveof <masterip><masterport>slaveof 192.168.8.8 6379

RunRedis

[Email protected]_slave ~]# redis-server/etc/redis/redis.conf

EnquirySlaveRun Log

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##AnalysisRedislog, you can seeSlavewith theMasterthe process of establishing a connection, data synchronization, such as: SendingSYNCcommand, withMasterEnd192.168.8.8:6379establish the connection, and thenSlave Sync started; thenMasterSendPINGcommand CheckSlavethe surviving state, replication is continued ....

querying all the databases in theKey

[[Email Protected]_slave ~]# redis-cli 127.0.0.1:6379> keys * (empty list or set)

3,3 Slave2The end operation is as follows:

[Email protected]_slave2 ~]# vim/etc/redis/redis.conf

# Add IP and Port of Slave Port , realize cascade replication;

# slaveof <masterip><masterport>slaveof 192.168.8.10 6379

#RunRedisService

[Email protected]_slave2 ~]# redis-server/etc/redis/redis.conf

EnquiryRedisRun Log

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## Results and Slave1 similar, but Slave2 with the Slave1 ( 192.168.8.10:6379 ) Establish a connection and synchronize the data; MySQL cascade replication is like this, master->slave1->slave2;

#querying all of the databaseKey

[Email protected]_slave2 ~]# REDIS-CLI

127.0.0.1:6379> keys *

(empty list or set)

3,4 MasterThe end operation is as follows:

[[Email protected]_master sh]# redis-cli127.0.0.1:6379> MSET ID 1005 namemariadb City beijingok127.0.0.1:6379> MGET ID name City1) "1005" 2) "MariaDB" 3) "Beijing" 127.0.0.1:6379> Keys *) "NAME" 2) "ID" 3) "City"

3,5client-side validation synchronization resultsSlave1-Side Verification

[Email protected]_slave ~]# redis-cli127.0.0.1:6379> auth [email protected] #aedf127 .0.0.1:6379> keys *) "City" 2 "Name" 3) "id" 127.0.0.1:6379> MGET ID NAME City1) "1005" 2) "MariaDB" 3) "Beijing"

Slave2-Side Verification

[[Email protected]_slave2 ~]# redis-cli127.0.0.1:6379> keys *] "id" 2) "name" 3) "City" 127.0.0.1:6379> MGET ID NAME C ity1) "1005" 2) "MariaDB" 3) "Beijing"

Four,Master Write,Slave Readmechanism

Redis Master-slave replication, through the program to achieve the separation of data read and write, the Master is responsible for processing the writing request,Slave is responsible for processing read requests, through the expansion of Slave processing more concurrent requests, reduce the load on the Master side, such as:

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This drawing is relatively simple, showing the realization Redis Read-write separation process, by judging the user read-write request, the write request sent to Redis Master processing,Read request sent to Redis Slave Treatment, the shortcomings of the article, welcome to the guidance.

This article is from the "Step by foot, from Ops to DBA" blog, be sure to keep this source http://cfwlxf.blog.51cto.com/3966339/1433637