Dividing Domains

This section will help you segregate your network into multiple domains without the need to register all of the domains on the internet. It also provides useful methods of separating your messaging system into divisions and organisations similar to the way NDS does.

We will use two examples to achieve similar results.

System 1: A school network

The school has a registered domain 'highschool.com'. The school network is divided into two organisational units as shown in the diagram below

To accommodate this network with a single registered domain we need to do a little bit of additional configuration within i-Mail as follows.

Firstly we will set up the domain 'highschool.com' as a normal domain in the Domains Tab. If the staff.highschool context is not a bindery context then we also need to set the Default NDS context in the UserLink Tab so that any mail that comes to the school is delivered, by default, into the staff OU. To limit who has access to e-mail, we can also add an access control group which will then only allow members of the StaffMailAccess group to get e-mail. We now have a fully configured mail system for the staff of 'HighSchool'.

Now we need to provide access to students. To do this we will 'fake' a domain called students.highschool.com within i-Mail. Once again under the Domains Tab, add a domain named students.highschool.com. This domain is independant so check the Independant box. Provide an access prefix of 'student' and enter the NDS context for this domain as 'students.highschool'. Unknown recipient handling should be set to go to the PostMaster.
Now that the students domain is set up, how do people send mail to these recipients? The e-mail address of the students needs to be configured slightly differently. We will use the format 'name.students@highschool.com' for e-mail that is destined for students. In the recipient replacement tab we set up i-Mail to convert any addresses that have .students appended to the name into our 'fake' domain. In the Recipient Replacement Tab, add a replacement with the following criteria:

*.students@highschool.com is replaced by %1@students.highschool.com

Now for anyone to send an e-mail message to GeraldE in the students context, the address will be GeraldE.students@highschool.com.

To send a message to Bronwyn, the address is Bronwyn@highschool.com.

This example shows a relatively simple multi domain setup where there is a single 'master' domain which all mail goes to by default.

System 2: A medium sized company

This company has a number of divisions with an appointed IT person in each division maintaining everyday minor details on the network such as printers and GP faults. The main system administrator is in his own department and controls the ongoing health of the network etc. The company has a domain registered as companya.com

In this system we will set up all of the domains as independant domains. The access prefix for each domain will be the name of the organisational unit, ie. the sales organaisational unit will use an access prefix of sales for retrieving mail. Each domain is in the format 'organisational_unit.companya.com'. A domain will not be set up for 'it' as this is our default domain. The domain for it.companya.com will simply be companya.com.

The domain 'companya.com' will have an access prefix of it and will, in effect, the global domain. We will set up a special replacement rule for this OU as it will have two effective e-mail address schemes.

For each domain we set up a replacement rule as follows:

*.organisational_unit@companya.com is replaced by %1@organisational_unit.companya.com

Our special case for the 'it' department is this replacement rule:

*.it@companya.com is replaced by %1@companya.com

This will allow any mail for either Ned@companya.com or Ned.it@companya.com to be send to the correct recipient. This is normally necessary if people sending e-mail know the structure of the organisation and provides a standard for mail delivery addresses.

For each domain we have set up we now need to add a PostMaster for each OU. We do this by simply entering the name of the person in the 'Forward To' field in the Domains Tab. This allows the 'local' administrator of that organisational unit to handle misspelt, misdelivered and area specific mail.