Indexing Service

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

An Indexing Service can manage simultaneously the indexes for many archives, which may be stored in different vault stores on different Storage Service computers. The computer on which you install the Indexing Service must have sufficient disk space to store the indexing data. The indexing data is held in indexes on the Indexing Service computer.

The indexes are organized as follows:

You specify during configuration (using the index storage location) where index volumes are to be created. If you want multiple index storage locations, you are recommended to spread them over different physical devices. (These locations are sometimes referred to as "index root paths" in error and diagnostic messages.)

If you specify more than one index storage location, indexes for new archives and new index volumes are spread over the locations.

You can choose how much information is indexed for items in an archive using the indexing level; this can be brief, medium or full indexing. If you want to be able to search item content for phrases, for example using Compliance Accelerator or Discovery Accelerator, then you need to use full indexing.

The more information that is indexed about an item, the easier it is to search for it. However, the more information that is indexed about an item, the more disk space is required for the index. Make sure you have sufficient disk space on the computer to store the indexing data. The size of index data for an item varies with the indexing level.

Table: Estimated size of indexing data shows the estimated size of an index as a percentage of the size of the item for the different indexing levels.

Table: Estimated size of indexing data

Indexing level

Estimated size

Brief

3%

Medium

8%

Full

12%

So, if you have allowed in the region of hundreds of gigabytes (or terabytes) of space for your vault stores, you are likely to require in the region of gigabytes (or tens of gigabytes) for your indexes.

The Indexing Service selected will be used for automatically-enabled archives associated with the target. Similarly, for SharePoint archiving, the Indexing Service selected for a target will be used for any auto-enabled site collection archives associated with the target.