Note: This page is quite old and is likely out of date. My opinions may have also changed dramatically since this was written. It is here as a reference until I get around to updating it.
yum install memcached -y
Memcached doesn't have a whole lot of configuration options. There is the user it's running under, what port it should listen on, what IP address it should bind too and how large it's cache is.
The default port is 11211 (TCP & UDP), and by default it will bind to
INADDR_ANY (0.0.0.0 and ::). Multiple addresses CAN be specified to bind too
-l flag. By default memcached will use 64Mb of memory.
These options can be set in
/etc/sysconfig/memcached. Here is mine which
restricts where it's bound too. For my general use 64Mb of storage is more than
enough (roughly the equivalent of 17.5k pages of plain text and these are
simple key value text pairs).
PORT="11211" USER="memcached" MAXCONN="1024" CACHESIZE="64" OPTIONS="-l 10.100.0.14"
By default memcached listens on both UDP and TCP port