The Zimbra server is a dedicated server that manages all of the mailbox contents, including messages, contacts, calendar, Documents notebooks, and attachments. Messages are received from the Zimbra MTA server and then passed through any filters that have been created. Messages are then indexed and deposited into the correct mailbox.
Each Zimbra mailbox server in the system can see only its own storage volumes. Zimbra mailbox servers cannot see, read, or write to another Zimbra server.
In a Zimbra single server environment, all services are on one server, and during installation the computer is configured to partition the disk to accommodate each of the services.
In a Zimbra multi-server environment, the Zimbra LDAP and Zimbra MTA services can be installed on separate servers. See the Multi-Server Installation Guide.
The regular license can only be installed on the ZCS system for which it is purchased. Only one Zimbra license is required for your Zimbra Collaboration Suite environment. This license is installed on the Zimbra LDAP server.
When you purchase, renew, or change the Zimbra license, you must update the Zimbra server with the new license information. Use the
Update License Wizard from the administration console’s Global Settings to upload and install a new license and to update an existing license, or you can install or update the license using the
zmlicense CLI command. See Appendix A, CLI Commands,
"zmlicense” on page 117 to use the CLI command.
The MTA server receives mail via SMTP and routes each mail message to the appropriate Zimbra mailbox server using LMTP. As each mail message arrives, the Zimbra server schedules a thread to have Lucene index it.
The Zimbra Message Store is where all email messages reside, including the message body and any file attachments. Messages are stored in MIME format.
The Message Store is located on each Zimbra server under /opt/zimbra/store. Each mailbox has a dedicated directory named after its internal Zimbra mailbox ID.
Single copy storage allows messages with multiple recipients to be stored only once in the file system. On UNIX systems, the mailbox directory for each user contains a hard link to the actual file.
Hierarchical Storage Management (HSM) allows you to configure storage volumes for older messages. To manage your email storage resources, you can implement a different HSM policy for each message server. Messages and attachments are moved from a primary volume to the current secondary volume based on the age of the message. The messages are still accessible.
The Zimbra Data Store is a MySQL database that contains all the metadata regarding the messages including tags, conversations, and pointers to where the messages are stored in the file system.
Each account (mailbox) resides only on one server. Each Zimbra server has its own stand alone data store containing data for the mailboxes on that server.
The index and search technology is provided through Apache Lucene. Each message is automatically indexed as it enters the system. Each mailbox has an index file associated with it.
Zimbra includes a configurable backup manager that resides on every Zimbra server and performs both backup and restore functions. You do not have to stop the Zimbra server in order to run the backup process. The backup manager can be used to restore a single user, rather than having to restore the entire system in the event that one user’s mailbox becomes corrupted. See
Backup and Restore.
Each Zimbra server generates redo logs that contain every transaction processed by that server. If an unexpected shutdown occurs to the server, the redo logs are used for the following:
When the current redo log file size reaches 100MB, the current redo log rolls over to an archive directory. At that point, the server starts a new redo log. All uncommitted transactions from the previous redo log are preserved. In the case of a crash, when the server restarts, the current redo log and the archived logs are read to re-apply any uncommitted transactions.
A Zimbra deployment consists of various third-party components with one or more Zimbra mailbox servers. Each of the components may generate its own logging output.
