There must be at least one Storage Service in an Enterprise Vault site. There can be only one Storage Service on a computer. If you want more than one Storage Service in an Enterprise Vault site, they must run on separate computers. It is usually best to put the Storage Service on the same computer as the Indexing Service.

Note that IIS must be installed on the same computer as the Storage Service.

If you anticipate that your archiving needs are great and require much storage, consider having more than one Storage Service in the site. This would require more than one computer running Enterprise Vault in the site.