The mailnickname attribute (or in Exchange nomenclature called “Alias”) in Exchange is similar to the Samaccountname in AD. Some of the characteristics are
- AD attribute name of Alias is “mailnickname”.
- Alias is the identifier for various Exchange processes as like in AD, logon name.
- All mail enabled objects should have alias field populated to be recognized as a mail enabled otherwise it is not considered as a mail enabled.
- RUS will first search for mailnickname and homeMDB attributes while identifying a mail enabled object to populate various attributes based on recipient policies.
- If you are planning to do directory sync to O365, mailnickname uniqueness is one of the items you will be asked to fix in your directory. Here are the best practice specifics for the mailnickname and required for O365 sync
- Maximum number of characters: 63
- Invalid characters: [ \ ! # $ % & * + / = ? ^ ` { } | ~ < > ( ) ‘ ; : , ] “ @
- The attribute value must not contain a space “ “.
- The attribute value cannot begin or end with a period (.).
- The attribute value must be unique within the directory.
- While it is best practice that the mailnickname match the email alias (the phrase before the “@” sign in email) it is not mandatory. So you could have
John.brown@tlkenterprise.com as the email
But the mailnickname can be jbrown
The better link is to have the mailnickname match the AD Samaccountname. The ideal scenario is when you have this
Samaccountname: jbrown
Email: jbrown@tlkenterprise.com
Mailnickname: jbrown
Mailnickname and Galsync
For Galsync when you bring in users from other directories and create them as contacts in your directory, I would advise that
- Check that the following is not violated
- Maximum number of characters: 63
- Invalid characters: [ \ ! # $ % & * + / = ? ^ ` { } | ~ < > ( ) ‘ ; : , ] “ @
- The attribute value must not contain a space “ “.
- The attribute value cannot begin or end with a period (.).
If any of these are violated, you can make changes via the extension code e.g. remove invalid characters, reduce the length to less than 63 etc.
- A uniqueness identifier should be added to the mailnickname. It could be the management agent name or it could be the business unit name. So
Remote Directory Management agent: AssetMgtMA
Mailnickname from AssetMgtMA: John.Brown
Mailnickname written to my AD: John.Brown-AssetMgtMA