You can monitor the following from the administration console.
Server status
Server performance statistics, including message count, message volume, anti-spam and anti-virus activity
Mail Queues
Server status and server performance statistics are available only if the Logger package is installed.
If the Logger package is installed, daily mail reports are automatically created. This report runs every morning at 4 a. m. and is sent to the administrator's email address. See the Administrator's Guide, Monitoring chapter for more information.
The Server Status Content pane lists all installed servers and services, including the services for MTA, mailbox, logger, SNMP, anti-spam, anti-virus, and LDAP. The status, 
for ON or 
for OFF, is displayed, along with the time the status last changed.
Server Statistic displays in a graphical format the message volume, message count, and spam and virus activity. The statistics are available for the last 48 hours and last 30, 60, and 365 days.
Mail Queues display a summary of the contents of the Deferred, Incoming, Active, and Hold queues on a Zimbra MTA server. You can view messages in a queue by domain and delete the contents of the queues by destination domain, origin IP address, or by specific types of errors.
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