To provide Zimbra is a hosted model how would one configure multi tenancy ?
For example we would like to
1> Configure multiple domains and assign an administrator for each domain. or,
2> Have one domain and have groups and group administrators?
Is the above possible out of the box or do we need additional some development ?
Also can a server have many domains ? and
can multiple servers manage the same domain ?
Server's can have unlimited domains. In the network edition there is 'domain admin' where you can assign an admin for 1 or more domains to manage basic tasks like create users, alias's etc.
All the routing is in LDAP so no matter which MTA the message gets to it will get to the right mail store.