[redis learning 13] redis builds master-slave cluster, sentinel cluster and partition cluster

Redis colony

This chapter is based on CentOS7 Under the Redis Cluster tutorial , Include ：

• Stand alone installation Redis
• Redis Master-slave
• Redis Fragmentation cluster

1. Stand alone installation Redis

Installation is required first Redis The dependence needed ：

yum install -y gcc tcl

And then Redis Upload the installation package to any directory of the virtual machine ：

for example , I put it /tmp Catalog ：

decompression ：

tar -xzf redis-6.2.4.tar.gz

After decompressing ：

Get into redis Catalog ：

cd redis-6.2.4

Run the compile command ：

make && make install

If there is no error , The installation should be successful .

And then modify redis.conf Some configurations in the file ：

#  Binding address , The default is 127.0.0.1, Will result in local access only . It is amended as follows 0.0.0.0 It can be in any IP visit 
bind 0.0.0.0
#  Protected mode , Turn off protection mode 
protected-mode no
#  Number of databases , Set to 1
databases 1

start-up Redis：

redis-server redis.conf

stop it redis service ：

redis-cli shutdown

2.Redis Master-slave cluster

2.1. Cluster structure

The master-slave cluster structure we built is shown in the figure ：

There are three nodes , A master node , Two slave nodes .

Here we will start in the same virtual machine 3 individual redis example , Simulate master-slave cluster , The information is as follows ：

IP	PORT	role
192.168.150.101	7001	master
192.168.150.101	7002	slave
192.168.150.101	7003	slave

2.2. Prepare the instance and configuration

To start on the same virtual machine 3 An example , Three different configuration files and directories must be prepared , The directory where the configuration file is located is the working directory .

1） Create directory

We create three folders , The names are 7001、7002、7003：

#  Get into /tmp Catalog 
cd /tmp
#  Create directory 
mkdir 7001 7002 7003

Pictured ：

2） Restore the original configuration

modify redis-6.2.4/redis.conf file , Change the persistence mode to the default RDB Pattern ,AOF Keep it off .

#  Turn on RDB
# save ""
save 3600 1
save 300 100
save 60 10000

#  close AOF
appendonly no

3） Copy the configuration file to each instance Directory

And then redis-6.2.4/redis.conf Copy files to three directories （ stay /tmp Directory execute the following command ）：

#  Mode one ： Copy one by one 
cp redis-6.2.4/redis.conf 7001
cp redis-6.2.4/redis.conf 7002
cp redis-6.2.4/redis.conf 7003

#  Mode two ： Pipe combination command , One click Copy 
echo 7001 7002 7003 | xargs -t -n 1 cp redis-6.2.4/redis.conf

4） Modify the port of each instance 、 working directory

Modify the configuration file in each folder , Change the ports to 7001、7002、7003, take rdb Change the file storage location to your own directory （ stay /tmp Directory execute the following command ）：

sed -i -e 's/6379/7001/g' -e 's/dir .\//dir \/tmp\/7001\//g' 7001/redis.conf
sed -i -e 's/6379/7002/g' -e 's/dir .\//dir \/tmp\/7002\//g' 7002/redis.conf
sed -i -e 's/6379/7003/g' -e 's/dir .\//dir \/tmp\/7003\//g' 7003/redis.conf

5） Modify the declaration of each instance IP

The virtual machine itself has multiple IP, To avoid future chaos , We need to be in redis.conf Specify the binding of each instance in the file ip Information , The format is as follows ：

# redis Instance declaration  IP
replica-announce-ip 192.168.150.101

Every directory has to be changed , We can finish the modification with one click （ stay /tmp Directory execute the following command ）：

#  Do it one by one 
sed -i '1a replica-announce-ip 192.168.150.101' 7001/redis.conf
sed -i '1a replica-announce-ip 192.168.150.101' 7002/redis.conf
sed -i '1a replica-announce-ip 192.168.150.101' 7003/redis.conf

#  Or one click modification 
printf '%s\n' 7001 7002 7003 | xargs -I{} -t sed -i '1a replica-announce-ip 192.168.150.101' {}/redis.conf

2.3. start-up

For the convenience of viewing the log , We turn on 3 individual ssh window , To start, respectively, 3 individual redis example , Start command ：

#  The first 1 individual 
redis-server 7001/redis.conf
#  The first 2 individual 
redis-server 7002/redis.conf
#  The first 3 individual 
redis-server 7003/redis.conf

After starting ：

If you want to stop with one key , You can run the following command ：

printf '%s\n' 7001 7002 7003 | xargs -I{} -t redis-cli -p {} shutdown

2.4. Open the master-slave relationship

Now the three instances have nothing to do with , To configure master-slave, you can use replicaof perhaps slaveof（5.0 before ） command .

There are temporary and permanent modes ：

• Modify the configuration file （ permanent ）

  • stay redis.conf Add a line of configuration ：slaveof <masterip> <masterport>

• Use redis-cli The client connects to redis service , perform slaveof command （ Failure after restart ）：

  slaveof <masterip> <masterport>
  

Be careful ： stay 5.0 Add new commands in the future replicaof, And salveof The effect is consistent .

Here we are for the convenience of demonstration , Mode 2 .

adopt redis-cli Command connection 7002, Execute the following command ：

#  Connect  7002
redis-cli -p 7002
#  perform slaveof
slaveof 192.168.150.101 7001

adopt redis-cli Command connection 7003, Execute the following command ：

#  Connect  7003
redis-cli -p 7003
#  perform slaveof
slaveof 192.168.150.101 7001

Then connect 7001 node , View the cluster status ：

#  Connect  7001
redis-cli -p 7001
#  Check the status 
info replication

result ：

2.5. test

Do the following to test ：

• utilize redis-cli Connect 7001, perform set num 123

• utilize redis-cli Connect 7002, perform get num, Re execution set num 666

• utilize redis-cli Connect 7003, perform get num, Re execution set num 888

You can find , Only in 7001 This master Write operations can be performed on nodes ,7002 and 7003 these two items. slave Nodes can only perform read operations .

3. Build sentry clusters

3.1. Cluster structure

Here we build a three node Sentinel colony , To supervise the previous Redis Master-slave cluster . Pictured ：

Three sentinel The example information is as follows ：

node	IP	PORT
s1	192.168.150.101	27001
s2	192.168.150.101	27002
s3	192.168.150.101	27003

3.2. Prepare the instance and configuration

To start on the same virtual machine 3 An example , Three different configuration files and directories must be prepared , The directory where the configuration file is located is the working directory .

We create three folders , The names are s1、s2、s3：

#  Get into /tmp Catalog 
cd /tmp
#  Create directory 
mkdir s1 s2 s3

Pictured ：

And then we were in s1 Create a directory sentinel.conf file , Add the following ：

port 27001
sentinel announce-ip 192.168.150.101
sentinel monitor mymaster 192.168.150.101 7001 2
sentinel down-after-milliseconds mymaster 5000
sentinel failover-timeout mymaster 60000
dir "/tmp/s1"

Reading ：

• port 27001： It is the present. sentinel The port of the instance
• sentinel monitor mymaster 192.168.150.101 7001 2： Specify the master node information
  • mymaster： Master node name , Customize , Write at will
  • 192.168.150.101 7001： The master node ip And port
  • 2： The election master At the time of the quorum value

And then s1/sentinel.conf File copy to s2、s3 In both directories （ stay /tmp Directory execute the following command ）：

#  Mode one ： Copy one by one 
cp s1/sentinel.conf s2
cp s1/sentinel.conf s3
#  Mode two ： Pipe combination command , One click Copy 
echo s2 s3 | xargs -t -n 1 cp s1/sentinel.conf

modify s2、s3 Configuration files in two folders , Change the ports to 27002、27003：

sed -i -e 's/27001/27002/g' -e 's/s1/s2/g' s2/sentinel.conf
sed -i -e 's/27001/27003/g' -e 's/s1/s3/g' s3/sentinel.conf

3.3. start-up

For the convenience of viewing the log , We turn on 3 individual ssh window , To start, respectively, 3 individual redis example , Start command ：

#  The first 1 individual 
redis-sentinel s1/sentinel.conf
#  The first 2 individual 
redis-sentinel s2/sentinel.conf
#  The first 3 individual 
redis-sentinel s3/sentinel.conf

After starting ：

3.4. test

Try to make master node 7001 Downtime , see sentinel journal ：

see 7003 Log ：

see 7002 Log ：

4. Build a cluster

4.1. Cluster structure

A fragmented cluster requires a large number of nodes , Here we set up a minimal fragment cluster , contain 3 individual master node , Every master Contains a slave node , The structure is as follows ：

Here we will start in the same virtual machine 6 individual redis example , Simulate fragment cluster , The information is as follows ：

IP	PORT	role
192.168.150.101	7001	master
192.168.150.101	7002	master
192.168.150.101	7003	master
192.168.150.101	8001	slave
192.168.150.101	8002	slave
192.168.150.101	8003	slave

4.2. Prepare the instance and configuration

Delete the previous 7001、7002、7003 These directories , Recreate 7001、7002、7003、8001、8002、8003 Catalog ：

#  Get into /tmp Catalog 
cd /tmp
#  Delete the old , Avoid configuration interference 
rm -rf 7001 7002 7003
#  Create directory 
mkdir 7001 7002 7003 8001 8002 8003

stay /tmp Next, prepare a new redis.conf file , The contents are as follows ：

port 6379
#  Turn on the cluster function 
cluster-enabled yes
#  The name of the configuration file for the cluster , We don't need to create , from redis Self maintenance 
cluster-config-file /tmp/6379/nodes.conf
#  Timeout for node heartbeat failure 
cluster-node-timeout 5000
#  Persistent file storage directory 
dir /tmp/6379
#  Binding address 
bind 0.0.0.0
#  Give Way redis Background operation 
daemonize yes
#  Registered instance ip
replica-announce-ip 192.168.150.101
#  Protected mode 
protected-mode no
#  Number of databases 
databases 1
#  journal 
logfile /tmp/6379/run.log

Copy this file to each directory ：

#  Get into /tmp Catalog 
cd /tmp
#  Execute Copy 
echo 7001 7002 7003 8001 8002 8003 | xargs -t -n 1 cp redis.conf

Modify... Under each directory redis.conf, Will be one of the 6379 Change to be consistent with the directory ：

#  Get into /tmp Catalog 
cd /tmp
#  Modify the configuration file 
printf '%s\n' 7001 7002 7003 8001 8002 8003 | xargs -I{} -t sed -i 's/6379/{}/g' {}/redis.conf

4.3. start-up

Because the background startup mode has been configured , So you can start the service directly ：

#  Get into /tmp Catalog 
cd /tmp
#  Start all services with one click 
printf '%s\n' 7001 7002 7003 8001 8002 8003 | xargs -I{} -t redis-server {}/redis.conf

adopt ps Check the status ：

ps -ef | grep redis

The discovery service has been started normally ：

If you want to shut down all processes , Can execute orders ：

ps -ef | grep redis | awk '{print $2}' | xargs kill

perhaps （ This is recommended ）：

printf '%s\n' 7001 7002 7003 8001 8002 8003 | xargs -I{} -t redis-cli -p {} shutdown

4.4. Create clusters

Although the service started , But at present, each service is independent , No connection whatsoever .

We need to execute the command to create the cluster , stay Redis5.0 It was troublesome to create clusters before ,5.0 Then the cluster management commands are integrated into redis-cli in .

1）Redis5.0 Before

Redis5.0 Before, cluster commands used redis Under the installation package src/redis-trib.rb To achieve . because redis-trib.rb Yes, there is ruby Language, so you need to install ruby Environmental Science .

#  Installation dependency 
yum -y install zlib ruby rubygems
gem install redis

Then use the command to manage the cluster ：

#  Get into redis Of src Catalog 
cd /tmp/redis-6.2.4/src
#  Create clusters 
./redis-trib.rb create --replicas 1 192.168.150.101:7001 192.168.150.101:7002 192.168.150.101:7003 192.168.150.101:8001 192.168.150.101:8002 192.168.150.101:8003

2）Redis5.0 in the future

We use Redis6.2.4 edition , Cluster management and integration into redis-cli in , The format is as follows ：

redis-cli --cluster create --cluster-replicas 1 192.168.150.101:7001 192.168.150.101:7002 192.168.150.101:7003 192.168.150.101:8001 192.168.150.101:8002 192.168.150.101:8003

Command specification ：

• redis-cli --cluster perhaps ./redis-trib.rb： Represents the cluster operation command
• create： The representative is to create a cluster
• --replicas 1 perhaps --cluster-replicas 1 ： Specify each node in the cluster master The number of copies of is 1, here Total number of nodes ÷ (replicas + 1) What you get is master The number of . Therefore, the top in the node list n One is master, Other nodes are slave node , Randomly assigned to different master

After running ：

Input here yes, Then the cluster starts to create ：

You can view the cluster status through the command ：

redis-cli -p 7001 cluster nodes

4.5. test

Try to connect 7001 node , Store a piece of data ：

#  Connect 
redis-cli -p 7001
#  Store the data 
set num 123
#  Reading data 
get num
#  Store it again 
set a 1

It turned out to be tragic ：

During cluster operation , Need to give redis-cli add -c Parameters only ：

redis-cli -c -p 7001

This time it's OK ：

The number of copies of is 1, here Total number of nodes ÷ (replicas + 1) What you get is master The number of . Therefore, the top in the node list n One is master, Other nodes are slave node , Randomly assigned to different master

You can view the cluster status through the command ：

redis-cli -p 7001 cluster nodes