Two types of administrator can be created for the Zimbra Collaboration Suite.
Global Administrator
Domain Administrator
Global Administrators are the primary administrators for the Zimbra Collaboration Suite and manage, monitor, and maintain the health of the ZCS email system. The administration tasks are performed either from the administration console or using the Zimbra command-line interface tools.
The major responsibilities include configuring the following:
Global settings that define the default global values for servers, accounts, COS, and domains.
Classes of Service (COS) that set the default attributes and features for user's mail accounts.
Domains settings, GAL settings, and authentication settings.
Server services, MTA, IMAP, and POP.
User accounts, aliases, and distribution lists, assigning either a COS to an account or configuring individual account's features and preferences.
Backup schedules so that in the event of a system failure, ZCS mail servers can be restored.
General maintenance and monitoring of the email system.
In addition, the Global Administrator can download and run the Migration Wizard to migrate Microsoft Exchange server email accounts to the Zimbra server and to import the mail and contact information for selected Exchange users.
The Global Administrator can delegate a user as a Domain Administrator and assign a specific COS to a domain.
A domain administrator can create accounts only for their domain and all tasks are performed from the administration console.
The Global Administrator configures the domain and assigns a COS to that domain. Accounts the domain administrator creates are automatically assigned the domain COS.
Domain Administrators manage the following tasks on their domain:
Provision new accounts, but they do not assign features or attributes. The domain COS is configured with the features and attributes for accounts.
Edit account information
Change passwords.
Change the status of an account
Create, delete, and move aliases
Create, modify, and delete distribution lists
Assign other users as a Domain Administrators
Download and run the Import and Migration tools
View mailbox quotas.
Set mailbox quotas (optional). The domain administrator can set mailbox quotas if the global administrator enables the domain admin configuration to modify the account mail quota.