install certbot on ubuntu 16.04

On Ubuntu systems, the Certbot team maintains a PPA. Once you add it to your list of repositories all you’ll need to do is apt-get the following packages. $ sudo apt-get update $ sudo apt-get install software-properties-common $ sudo add-apt-repository ppa:certbot/certbot $ sudo apt-get update $ sudo apt-get install python-certbot-apache Reference: https://help.ubuntu.com/community/Repositories/Ubuntu#Adding_PPAs

protect zimbra from memcached attack

Zimbra uses memcached and if not properly configured could lead to a vulnerable system. If you want to read more on memcached attack read this: https://blog.cloudflare.com/memcrashed-major-amplification-attacks-from-port-11211/ How to resolve this vulnerability in 3 steps: Enable firewall on your server Setup zimbra specific rules Bind memcached to localhost Deny memcached port from localhost Let’s start.