redisHA

Solution of redis failover, read/write separation, and read load-balance. Total client-independent

What can it do

• Let your redis master/slave failover automatically
• Switch clients to the new master when failover happens
• read/write separation
• Read traffic load-balance (among slaves or all servers)
• No multi-master problem (compare to legacy HAProxy redis check)
• Total client-independent, doesn't require any client libraries

Prerequisite

• Redis
• HAProxy (community edition is enough)

How to use

Depoly a 3-server redis enviorment (1 master, 2 slaves)

For this part, you can find further instructions at https://redis.io/topics/replication

Deploy 3 sentinels

1. Make 3 copies of sentinel.conf. Modify them, replace properties surrounded by angle brackets with real ones.
2. Start 3 sentinels

redis-sentinel ./sentinel.conf

Run HAProxy

1. Modify haproxy.cfg, replace properties surrounded by angle brackets with real ones, and make changes accord to comments if needed.
2. Start HAProxy

haproxy -f ./haproxy.cfg

Then it's done

just let your clients use HAProxy's 16379 port for writes and 16479 port for reads

How to test failover

Connect to current master, execute command:

DEBUG sleep 10

the failover should happen after 8 secs, then you can visit http://:8888/haproxy?stats to see if HAProxy's stat changes

More to do

Make your HAProxy able to failover (keepalived recommended)