Businesses operate on a global scale: Enterprises station offices in major U.S. cities, European capitals and Asian...
megaregions. As a result, data generated in one time zone has to be updated quickly -- in some cases immediately -- in a handful of others. To meet such challenges, organizations have to overcome numerous obstacles.
With employees in diverse locations, enterprises must decide how to build a dispersed Exchange Server setup, so data moves freely. Exchange server placement creates a series of trade-offs. Centralizing servers can reduce overall costs by maximizing system usage and simplifying management; however, response time may become an issue because users and systems are located far apart.
Installing servers as close as possible to employees cuts down on the time it takes for workers to interact. Latency decreases and response times improve because the email infrastructure -- servers, storage and network devices -- is near the endpoints.
Solving Exchange Server replication problems
The challenge with installing Exchange servers near employees is to replicate the information. The IT organization must coordinate data at dispersed sites. If an employee in Germany leaves the company, the server in Australia must know to remove the person's system credentials.
Companies can complete such updates in one of two ways. Synchronous communication means that everyone works from the same data set. The downside is changes are entered only if connections are available to all servers. A bottleneck in one location prevents the needed system update globally. Asynchronous connections make updates as links become available. The system enables users to make changes immediately; the downside is two contradictory entries may be entered.
Determining required processing power
Another issue is determining how much processing power each Microsoft Exchange server needs. In this case, the IT team undertakes a series of evaluations:
- How much information should users store in mailboxes?
- How quickly should they be able to access that information?
- How many mailbox database copies are needed?
- How much storage is needed?
- How much larger will the system become?
- Is the system connected to any other applications?
- Will the firm use any third-party add-ons, and how do they affect performance?
It can prove challenging to make these determinations because estimates can vary dramatically. Some users receive a handful of messages daily, and others hundreds. The average message size also differs. Typically, companies work with text-based messages that are in the 50 kilobyte range, but firms that handle graphics or video files routinely move several megabytes of data over Exchange.
One way to determine an estimate is to examine message tracking logs. They outline how many messages are generated and the size. In addition, Microsoft provides a few tools to help enterprises with configuration issues. The Exchange Server Role Requirements Calculator helps companies size servers. The calculator determines if the user needs items, such as dedicated Client Access software, and evaluates factors, such as network performance. The Microsoft Exchange Server Jetstress 2013 Tool simulates Exchange disk I/O load on a server to verify the performance and stability of disk subsystems.
Microsoft also provides a tool to help companies ensure a viable Exchange Server setup. Despite some confusion with the name, the Office 365 Best Practices Analyzer for Exchange Server 2013 can be installed to test on-premises Exchange servers. The tool scans servers and identifies potential configuration items, such as database health, poison mailboxes and the results of mixed systems.
System costs are a major factor
Cost plays a big role in how businesses develop an Exchange Server setup. A distributed system introduces new expenses: System hardware -- server, storage, network equipment -- and personnel are replicated in at least one location. Typically, corporations run a backup system, which makes justifying two global data centers possible.
When a company needs more sites, the economics have to be sound. Calculating the costs of a distributed Exchange deployment can be complex and involve evaluating many factors that vary by organization. For instance, in addition to more hardware, software and personnel, the additional data center(s) introduces new energy and facility expenses.
The potential savings from a dispersed Exchange Server setup come from a few areas, starting with reduced network expenditures. Using 10 GbE connections, which often are used to connect company locations, creates a recurring monthly expense. The prices for a link to the local carrier range from a few thousand dollars to about $20,000 per month and rise depending on end point distance, according to telecom market researcher TeleGeography. Improved productivity is another potential gain. Because network latency is reduced, users wait less and can work more.
Addressing time zone problems
International communication creates management challenges. Employees need to be aware of time zone differences. Consider placing clocks with different time zones in the data center, so everyone can see what the time is in a remote office. Shared calendars enable employees to understand who is where at various times and plan accordingly.
Employees access email 24/7, so IT support help needs to be available consistently to global organizations. A person in Australia may need help when the New York support team is the first line contact. The firm has to ensure the Australian employee can connect with coworkers in New York. A firm also needs to overlap support times so there is coverage as one shift leaves and another comes to work.
Dispersed locations mean local holidays. In some cases, a national holiday, such as the Fourth of July in the U.S., shuts down one country. European workers cannot be left in the lurch. Support staff and other employees should be aware of all observed holidays. Email blasts, internal message boards and social media notifications help workers understand and plan for any local breaks.
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