Make generated names unique
Uniqueness tab
Check a generated value against the target fields that must be unique, then define which candidate NIM should try when the first is already in use.
At a glanceDirect link to At a glance
Build the output on the Names tab before configuring Uniqueness. For a username, email address, or other unique identifier, select the system fields that NIM must check for an existing value. NIM tries the name's methods in order and can use an iteration to produce further candidates when needed.
| Decision | What to check |
|---|---|
| Which name needs checking? | Select the output used for the target identifier; display names may not need a uniqueness rule. |
| Where can a collision occur? | Select every relevant system field in Fields, including another field that could already hold the same kind of value. |
| What happens after a collision? | Put the preferred method first, then add fallback methods or an iteration in the order you want NIM to try them. |
For example, if schen already exists, a later method might produce sachen. A numeric iteration can then offer sachen1, sachen2, and subsequent candidates. The actual result depends on the source record, method order, selected fields, and existing target data.
Enforce uniqueness for namesDirect link to Enforce uniqueness for names
Use uniqueness checking when a target value, such as userPrincipalName, must not collide with an existing account value. Confirm the target system has been collected recently enough for the selected fields to reflect existing records.
Select the fields to checkDirect link to Select the fields to check
- Edit the name generator and open the Uniqueness tab.
- Select a name in the Names pane.
- In Fields, select every system column that must not contain the generated value.
Prepare candidates for collisionsDirect link to Prepare candidates for collisions
Return to Names to add methods in the order NIM should try them. Add an iteration to a part in the last method when you need more candidates. Then revisit Uniqueness to confirm the correct name and fields are selected.
| Fallback | Example |
|---|---|
| Another method | schen → sachen using a middle initial. |
| Character-length iteration | S → St → Ste. |
| Numeric iteration | sachen → sachen1 → sachen2. |
Resolve collisions during mappingDirect link to Resolve collisions during mapping
Save the generator. When a mapping runs, NIM checks the selected fields and tries each method or iteration until it finds an available value. Test with a safe record whose first candidate is already in use, then inspect the resulting mapped value and job result before scheduling the mapping for a larger population.
A name that does not need to be unique needs only one method. Names that are synchronized must have the same number of methods.
If no candidate is availableDirect link to If no candidate is available
Check that the selected fields represent the values you intend to protect, that the source filter returns the expected record, and that the method order and iteration offer enough candidates. NIM has a shared maximum iteration count in Service Settings; reaching it produces an error rather than another candidate. After correcting the rule, preview and test a limited mapping again.
Continue with Multi-value names when one target attribute needs several generated values, or return to the name generator overview.