Zimbra memcached may face the “memcrashd” attack on port 11211. By default, memcached listens on a server IP address that is accessible on the network and via the internet if there is no firewall.
If your Zimbra memcache servers are behind a firewall, we recommend blocking access on port 11211 from the Internet to Zimbra memcache servers. Once done, you do not need to follow further steps in this wiki.
If your zimbra memcache server is NOT behind a firewall and is accessible over the Internet, then proceed with the steps in this wiki.