Do not create the first Index Server group before you are sure that Index Server groups will benefit your Enterprise Vault site.
See About Index Server groups.
See Do I need to create Index Server groups?.
To create an Index Server group
In the Administration Console expand the Enterprise Vault container.
Expand the Directory container.
Expand the Enterprise Vault site.
Expand the Indexing container.
Right-click Index Server Groups and on the shortcut menu click New and then Index Server Group.
The New Index Server Group wizard starts. If there is only one Index Server in the Site there is a message that explains that there may be no benefit from an Index Server group. Click Continue if you are sure that you want to create an Index Server group.
The wizard introduction page refers you to documentation for information about Index Server groups.
See the section "About Index Server groups" in the Introduction and Planning manual.
Click Next to go the Name and Description page.
Enter a Name for the Index Server group and optionally a Description. You can change the Name and Description at any time.
Select the Index Servers that you want to add to the new Index Server group. There is no requirement for you to add the Index Servers now. You can add Index Servers later, as required.
If you have chosen to add Index Servers to the new Index Server group you can now choose to associate vault stores with the new Index Server group.
When you add an Index Server to an Index Server group, its associated vault stores are not included automatically. Enterprise Vault does not index those vault stores unless you associate them with an Index Server group. If you want those vault stores to be indexed by the new Index Server group, select All Vault Stores that are currently indexed by the servers you have chosen to add to the new index server.
Click Next. The page shows the details that you have entered.
Click Create Index Server Group. The wizard creates the new Index Server group and shows a summary page.
Click Close to close the wizard.
If you did not add an Index Server to the new Index Server group you can edit the properties of the Index Server group to do so.
See Adding an Index Server to an Index Server group.