Options on the Appliance Manager Web Server Acceleration pages and the Streaming Server Acceleration pages enable you to carry out operations related to acceleration. These operations are described in the following sections.
When you create Web acceleration rules, you specify the Web server or servers to accelerate, and you assign the accelerator or virtual accelerator hosts on this appliance to accelerate them.
For example, the following rule maps HTTP requests directed at a specified IP address and host name on the accelerator to the DNS-listed host name and HTTP-defined host name on the Web server from which the requested object will be fetched. Accelerator access to a DNS lookup server is required.
For information about creating and editing Web server acceleration rules, see the Appliance Manager online Help.
When you create or edit a Web server acceleration rule, you can number that rule to specify the order in which it is applied in relation to other rules. In case of conflicting rules, the earlier-numbered rule is applied.
For information about creating and editing Web server acceleration rules, see the Appliance Manager Help.
When you create or edit a Web server acceleration rule, you can specify a number ID for an optional log file which this accelerator generates especially for logging accelerator-server transactions generated by this rule.
If no value is specified, then the accelerator-server transactions generated by this rule are logged in the general Web access log.
If you have multiple rules for multiple Web servers, you can specify a different Web acceleration log number for each rule.
For information about creating and editing Web server acceleration rules, see the Appliance Manager Help.
When you create streaming acceleration rules, you specify the streaming server or servers to accelerate, and you assign the accelerator or virtual accelerator hosts on this appliance to accelerate them.
The following rule directs the accelerator to fetch requested streaming objects through port 554 from the streaming server backplace.org in response to RTSP streaming requests directed to IP address 132.132.10.10, port 554, and host frontplace.org on the accelerator.
The following rule directs the accelerator to fetch requested streaming objects from the streaming server at IP address 132.10.10.15, port 1755, when requests are directed to IP address 132.132.10.10 and port 1755 on the accelerator.
For more information about creating and editing streaming server acceleration rules, see the Appliance Manager online Help.
The following rule directs the accelerator to fetch requested streaming objects from the streaming server at IP address 132.10.10.15, port 1755, when requests are directed to IP address 132.132.10.10 and port 80 on the accelerator.
The appliance did not support server-side HTTP encapsulation in releases prior to NetCache 5.3.1. Therefore, to accelerate HTTP-encapsulated MMS data in earlier releases, you must construct acceleration rules as follows:
132.132.10.10 80 * * 132.10.10.15 80 * *
You can write ACL rules to accept or deny access to the requested content through the accelerator. For example, the following access control denies the client with IP address 128.126.10.0/24 from accessing the Web or streaming accelerator:
deny client-ip 128.126.10.0/24
For information on writing ACL rules, see the Appliance Manager online Help.
If you are using ContentDirector to prefill content, you must use the URL of the origin server as the target URL of the ContentDirector push. Otherwise, your clients cannot access the prefilled content. The reason for this is that content must be cached under the URL of the origin server so that cache misses can be resolved from the origin server.
For example, the following acceleration rule correctly directs the Web accelerator to search for content that includes the URL of the origin server:
accelerator-ip 8080 * origin-server-ip 8080 *
Given the preceding rule, if you prefill (cache) content using the IP address of the Web accelerator, clients will not be able to access content. For example, consider content that is prefilled as follows:
http://accelerator-ip/foo.html
Because the acceleration mapping rules direct the appliance to look for content cached under the IP address of the origin server, your prefilled content will never be found.
You can configure the appliance to monitor for a transition in the status of Web servers or streaming servers that it is accelerating. When an accelerated server changes from an up state to a down state or from down to up, the appliance logs a syslog message and sends an SNMP trap if such a trap has been defined.
If a Web server is down, the appliance in monitor state will continue to serve freshly cached Web objects or return 404 (Not Found) codes for uncached or stale objects.
For details, see the Appliance Manager online Help.
You can limit the IMS (If-Modified-Since) queries that the appliance sends to accelerated Web servers on cached Web objects through the IMS optimization option.
Select Setup tab > HTTP > Web Server Acceleration and locate the IMS optimization option. Click the Help icon for details.
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Part No. 210-00369
File: accel8.htm
Last updated: 11/12/02 12:13:53