Exchange Server Database Storage Management

Every one of us, want our data to be handled in an organized way. A better organizing architecture gives better search results, avoids the destruction of files, etc. Before the introduction of Microsoft Exchange Server it was difficult to maintain transaction log and record of emails. But, due to the development of this software, it has become flexible to keep backup of email communication. Different architectures follow different schemas for file storage and their management. Likewise, Microsoft Exchange server stores available data in two file formats:

• .edb  file
• .stm file

EDB File Extension:

EDB is one of the files for database created by Microsoft Exchange Server software. The file with .edb extension contains tables for holding metadata, email messages, and other items in the Exchange store. EDB file is used to store MAPI messages, and is referred as MAPI database. For long runs, if you want to store the EDB file, you can do that simply by converting EDB files into PST file. As it is easy to maintain a record of EDB file in PST format due to their local accessibility unlike Exchange database which is server dependent. It is recommended to use third party tools for carrying out the conversion of EDB to PST.
Note: EDB file is a product of Microsoft. No one can change, modify, or access the mails without accessing Exchange server.
If a user wants to access his mail from a system when he is not connected to the server, then it is advised that he converts the EDB file into PST file. Now this output PST file after conversion can be accessed from anywhere on a system with Outlook of any version installed along with internet connection. Many third party tools are available for executing such a conversion in the online market and these tools for EDB conversion are very effective.

OPENING EDB FILE

Exchange Server 2007 and Earlier Versions
C:\Program Files\Exchsrvr\MDBDATA

Storage Location

STM FILE EXTENSION:

As you can see in the image above, encircled along with the EDB file is an STM format file. An Exchange Server Streaming file is created and used by the Microsoft Exchange Server Software. These STM files store data in database with certain encoding specification, in a format which is also developed by Microsoft. The file with .stm extension contains streaming Media files and native web content. Consider a situation where whenever a MAPI client wants to access an email or media file stored on the Exchange Server it can be accessed from the .stm file associated with EDB files.

EDB and STM Files: Further Divided 

Public Folder: (pub1.edb, pub1.stm)
Public folder is responsible for holding all the emails or items available for sharing among all the clients in connection with the server.
Private Folder: (priv1.edb, priv1.stm)
Private folder contains emails, and other items of a private user account and are non shareable.

Note: .stm files are not supported by Microsoft Exchange Server 2007 and later versions.

EDB and STM are usually found in a single folder as a pair. The files or the transactions carried out in it are recorded in a transaction log, similar to the way it is done in a traditional database file. Changes in database will be reflected only after the completion of the transaction; otherwise, the transaction is aborted or rolled back. The uncommitted log Transaction is also considered as an entry in the log as part of the current Exchange Database. Exchange server storage architecture works similar to that of a traditional database for transaction management.

The whole architecture basically manages the transaction log and provides protected storage schema for the database. For the management of transactions, Microsoft Exchange Server offers the Information Store Service facility.