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3 Node (Master Slave Slave) Redis Cluster with Sentinel

It is possible to make your Redis cluster Fault Tolerant and Highly Available by building a replica set and then monitor these nodes using sentinel for automatic failover.

I am going to give an example setup to explain it. The structure is built with three nodes running one as a master and two as slaves.

Master Node: (Centos 7.2)
Slave1 Node: (Centos 7.2)
Slave2 Node: (Centos 7.2)

Edit System settings on each node: /etc/sysctl.conf

Disable transparent hugepage (transparent_hugepage=never) on each node: /etc/default/grub

Apply grub config and reboot each node:

Master Node: /etc/redis/6379.conf

Slave1 Node: /etc/redis/6379.conf

Slave2 Node: /etc/redis/6379.conf

Master Node: /etc/redis/sentinel.conf

Slave1 Node: /etc/redis/sentinel.conf

Slave2 Node: /etc/redis/sentinel.conf

Each Node: /etc/systemd/system/

Each Node: /etc/systemd/system/

After creating service files reload systemd and enable,start related services on each node:

Check replication and sentinel status from redis-cli Master and slave nodes:
Master Node:

Slave Node:

Master Node:

Stop wait and start Redis Master and check logs on a slave:
Master Node:

Slave1 Node:

Now redis master is failed over another node.


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