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E-Guide: Exchange Server Maintenance and Security Issues
As with most applications, the Exchange server platform has maintenance and security issues. While these issues can create serious problems if left unchecked, there are options for enhancing the protection and performance of your Exchange server.
Security Issues
There are several vulnerabilities in the Exchange server platform that can result in security issues. These vulnerabilities can lead to unauthorized access to data, including the ability to alter or steal the accessed data. The following are some of the more common vulnerabilities:
Denial of Service (DOS) Attacks - DOS attacks interfere with the delivery service functions in Exchange, to the point that users lose the ability to use any of the collaborative functions. This is typically accomplished in one of three ways:
1. Exploiting bugs in the Exchange program that will cause the server to crash
2. Exploiting certain inefficient processes in the Exchange program by causing the to run repeatedly, disrupting service
3. Using a specially formatted email to cause Exchange to begin automatically sending acknowledgement emails, to the point that these emails flood the server and clog the messaging system.
Access Rights - Exchange server has vulnerable points in authorization and access to the system. Because an administrator is able to read messages in any user's account, a specific administrator account, created during setup, can be taken advantage of by those who want to exploit Exchange. In addition, Exchange does not correctly authorize and authenticate users for certain functions, creating an opening for attacks.
Viruses - Because Exchange has a problem with unchecked buffer overruns, it is vulnerable to any virus that exploits overruns. An unchecked buffer is a bug in the program script caused by the programmer's failure to set up enough memory space for the program to read input. When there is not enough space, the input information runs over into application memory, overwriting some of the code. Some viruses take advantage of this by causing the new code to execute specific actions, such as crashing the system or destroying data.
Information Leaks - The Exchange server platform provides details about the server while it is running. That information can be used to a hacker's advantage when attacking the server.
On the bright side, there are techniques that prevent a vulnerability from becoming an exploited weakness. Proper firewalling of the server can help prevent unauthorized access, both by end users and outside attackers. Advanced virus scanning and spam filtering tools can help keep a virus from infecting the system and exploiting vulnerabilities in the Exchange server platform. Finally, timely installation of security patches, as well as appropriate upgrades, can solve the vulnerability issues before they become a serious problem.
Maintenance Issues
Routine maintenance of the Exchange server is necessary in order to maintain productivity and avoid slowed emails or a complete system failure. While the Exchange server does have a built-in maintenance routine, this routine is only the most basic process required to keep information operations running smoothly.
Without proper maintenance, the Exchange server gradually degrades until it eventually fails completely. As the Exchange server begins to degrade, users will encounter an increasing number of errors and warnings. In addition, the information stores will randomly go offline and come back. At times, the system will completely shut down.
Regular, routine maintenance should include checking for and correcting errors, as well as re-indexing and defragmenting the database. The re-indexing and defragmenting processes will clean up any white space on the server and permanently remove deleted items. This also serves to reduce backup time, which will prove beneficial if there is ever a need for disaster recovery.
The main issue with maintenance of the Exchange server is the time and cost of regular maintenance. The maintenance process requires staff and time, both of which increase a company's overhead. In addition, routine maintenance requires the Exchange server to be taken offline, further costing time and productivity.
Other than ignoring maintenance completely, which is not generally seen as an option, there are two possible solutions The first option is to take servers offline at night, while messaging is not being used, to complete the maintenance process. While this still requires staff and man-hours, it keeps the maintenance from causing downtime.
The other option is to use an automated system for maintenance. An automated program can be scheduled to run routine maintenance procedures whenever it is most covenient. For example, it can take a server offline in the middle of the night, check for and correct errors, perform backup, then re-index and defragment the database before putting the server back online. The program can do this with as many, or as few, Exchange servers as you need, and it can be scheduled to the maintenance on a regular basis.
Regardless of whether you host your Exchange server or have it hosted for you, routine maintenance and security measures are necessary for prolonging the life of the server. If hosting your own server, take appropriate measures for ensuring maximum productivity. If using a hosting solution, be sure to find out about the hosting company's security and maintenance measures before signing the contract.