Zimbra Patching – Recommended Best Practices 2019

During yesterday’s Zeta Alliance call, Zimbra Patching, recent Zimbra exploits and their mitigation were a featured topic of discussion.  The Zimbra forums have some very active discussions about mitigating currently compromised systems, so I thought it would be timely to summarize the current status of the current compromise, Zimbra’s reactions …

Java Improvements Make Upgrading Zimbra Attractive

Zimbra 8.8.12 quietly replaced Java 8 with Java 11, and combined with a change in Java Garbage Collectors, we are seeing significant mailbox server performance improvements just from doing an upgrade to 8.8.12. Key Takeaway If your mailbox servers are swapping but you believe you should already have sufficient RAM; …

Zimbra on Amazon Web Services – Disk Reference Architectures (Updated April 22, 2019)

Executive Summary During the past year I have migrated a number of Zimbra systems to Amazon Web Services (“AWS”).  These “real-world” experiences led to my being invited by Zimbra to present my AWS Hosting Best Practices at their North American Partners’ Conference in Dallas, Texas in October 2018.  (You can …

Using Zimbra’s DoSFilter and Failed Login Lockout Policy Together

Zimbra’s DoSFilter (Denial of Service Filter) is a mechanism to throttle or block IP addresses that have a repeated number of failed logins to your Zimbra system.  Zimbra’s Classes of Service include a Failed Login Lockout policy that will put a mailbox in Locked Out mode, hopefully before a brute …