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 …

Zimbra Unattended Upgrades – Yes or No?

Security vs. Stability One challenge facing Linux system administrators is the tradeoff between security and the potential loss of stability when considering whether or not to enable “unattended upgrades”. When enabled, the operating system self-updates and reboots as necessary whenever package updates are released. In the case of public-facing Zimbra …