Memcached is available in the base repo, and can be installed by just typing:
yum -y install memcached
Lets look at the config:
It should look like this
By default we can see that it listens on port 11211, and runs as a user named memcached which was created by the RPM install via yum. You can also tune the max number of connections to the cacheing service, and the size of the cache (64MB by default).
There is no authentication with memcached, and by default it listens on all interfaces. You do not want this service to run on an untrusted network unless you have firewall rules in place that you have extreme confidence in. You can also choose to run on localhost so only the local app/webserver will use it. To do this, change the OPTIONS= to this:
Once the service is running and apps are using it, you can see the cache slabs, show general stats, and dump key and values using memcached-tool.
# show slabs
memcached-tool 127.0.0.1:11211 display
# view general stats
memcached-tool 127.0.0.1:11211 stats
# dump the key/value pairs
memcached-tool 127.0.0.1:11211 dump