As the Internet grows in terms of the number of users, number of transactions, and amount of traffic, so does the size of the infrastructure and servers required to support Internet-based services. To be able to scale Internet services successfully, the operating system must be able to respond to the increasing load, both within the constraints of a particular piece of hardware and through the use of distributed computing technology such as clustering, network load balancing, and transaction services.
To manage the network resources for an individual server you can use the Solaris Bandwidth Manager, which allows you to configure the available network bandwidth on Wide Area Network (WAN) connectivity on an application and/or user basis. For example, you could allocate a significant proportion of the bandwidth on an Internet link to the HTTP protocol, ensuring maximum throughput when supporting Web applications. However, the settings are fixed according to individual protocols and machines—there is no load balancing between multiple machines
In addition, a single server can be configured to provide performance and services to specific applications. Using Processor Sets, a multi-processor server can assign groups of processors to handle individual applications. This ensures that mission-critical applications gain the maximum performance without sacrificing individual CPU performance to non-critical tasks.
Using Solaris Domains, a SPARC-based SMP server such as the Sun Enterprise 10000 (Starfire) can be configured to appear as one or more physical machines. Configuring each of the Solaris Domains is dynamic. For example, during the day the system can be configured to provide maximum performance to the client-facing e-commerce application, but during the night the system can be set to be reconfigured to provide the best support for batch jobs, replication, or backup systems, without entirely disabling the e-commerce site, which can continue operating.
For performance-intensive or mission-critical sites, you can use Sun Cluster Manager to support a 4-node fail-over cluster using Solaris 8 Enterprise Server. The cluster can be configured either to ensure scalability and availability or reliability. When used in combination with the Solaris Resource Manager, the cluster can be configured to maximize the available resources on all servers. For resilience, any individual server within a cluster can replace a failed server with only a small loss in availability.
Windows 2000 Server supports advanced resource management either through the API used to build the applications or, in the case of Windows 2000 Datacenter Server, you can use Process Control tool. This tool allows you to control how individual applications access and use individual resources. The tool uses the Job Object API (present in all Windows 2000 server versions), which can be used to define one or more processes as a single identifiable unit. A system administrator can define rules that control the individual resource usage for a Job Object. For example, you might throttle the CPU or RAM available to non-critical applications. The Process Control system also provides scheduling and priority control on individual processes and process groups.
Windows 2000 also supports multi-processor systems and, using either the Advanced or Datacenter Server, clustering of individual systems up to a maximum of four nodes. Support for two-node clustering is provided in Advanced Server, while Datacenter Server supports 4-node clustering.
Windows 2000 supports a Network Load Balancing Service (NLBS). NLBS allows Windows 2000 to distribute TCP/IP requests to any of up to 32 servers or clusters within a network. Rather than restricting the choice to a simple round-robin system of distribution, or throttling bandwidth to individual protocols on each server, NLBS monitors the load on each server and automatically allocates new requests to the most appropriate machine. In addition, NLBS allows for establishment and servicing of multiple NLBS clusters.
Using NLBS it is possible to handle multiple requests across an entire server farm whether you are using individual machines or multiple clusters. In each case, NLBS will make the best use of the available resources across the entire server network without resorting to controlling servers on an individual or protocol basis. In addition, it is possible to have multiple NLBS clusters
Although Solaris 8 provides tools for controlling the network bandwidth and resource use within a server farm, until the recent acquisition of a third party application by Sun, there was no way of managing application performance across a network for Internet services. Windows 2000 supports all of the resource management features offered by Solaris 8, as well as the ability to control the performance of the network as a whole.
Internet Service Management
Management of Sun WebServer services on Solaris 8 is handled through a Web-based management tool called the Sun WebServer Administration Console. Although the interface may be practical for remote management, it has significant limitations.
Because there is no integration between individual Internet services on Solaris, each service can have its own administration interface. For most services, the only interface provided is through a command line interface. Although this is compatible with a remote connection, it is less than ideal for most services. To further complicate matters, because the different services use different management tools the administrator needs to be an expert on a number of different systems.
The lack of integration also means that the effects of managing one service do not automatically notify the other services. For modern Internet applications this can have serious ramifications, including loss of service and even data inconsistency or corruption.
Windows 2000 Server uses the new Internet Information Server (IIS) 5.0, which provides operating system level functionality for the main Internet services. IIS 5.0 can be managed using the Microsoft Management Console (MMC), a unified management tool that supports remote management of all services across both local and remote instances of IIS.
Because Internet service support is built into the operating system using IIS, all aspects of your Internet service can be managed from a single console, either locally or remotely. This includes http, FTP, SMTP, and NNTP services. For remote management, you can also use an HTML-based administration tool allowing control of services from any frame and script-capable browser. By using a combination of wizards and traditional property dialogs, Windows 2000 and IIS make it possible for any computer-literate user to set-up and manage Internet services.
Table 5 below compares Internet Management Services.
Table 5: Comparing Internet Management Services
|
Service
|
Solaris 8 Easy Access Server
|
Solaris 8 ISP Server
|
Windows 2000/IIS 5.0
|
GUI Website Management
|
N
|
N
|
Y
|
GUI Mail Server Management
|
N
|
N
|
Y
|
GUI Directory Management
|
N
|
N
|
Y
|
Web-based Web site Management
|
Y
|
Y
|
Y
|
Web-based Mail Server Management
|
N
|
Y
|
Y
|
Web-based Directory Management
|
N
|
Y
|
Y
|
Command-line management tools
|
Y
|
Y
|
Y
|
| 