Features

+ maintains persistent upstream connections
+ keeps low connection count on upstream servers
+ deals with upstream failures
+ supports SET, GET, SETEX, DEL, INCR, DECR, EXPIRE, EXISTS commands

Build

install jruby (tested with 9.1), then:

$ bundle install
$ warble compiled jar

Configure

create config.yml with the following content

log_level: 'debug'

server:
    -
        type: 'cluster'
        listen: '127.0.0.1:26379'
        buffer: 16384
        timeout: 1
        upstream:
            - '127.0.0.1:6379'

Run

$ java -jar redis-proxy.jar