One slightly lengthier approach is to have the following.
Create a simple script(may be in python) which does "info" on all the nodes and "cluster info" after connecting to one node every minute, gets the data, and pushes it into the graphite. After that you can use grafana to create the monitoring graphs based on all parameters that you get from the above commands.
The above can be used for monitoring the performance of redis.
Also, you can have another script which does a simple dummy insert, like redis-cli -c -h <host> -p <port> set testkey testVal, and if it fails, the script will send a mail to someone.
A combination of these two can be used to monitor redis...or atleast that is what we have done.