Rewrite Policy Label Test

Rewrite refers to the rewriting of some information in the requests or responses handled by the Citrix ADC appliance. Rewriting can help in providing access to the requested content without exposing unnecessary details about the Web site’s actual configuration.

To rewrite the HTTP or TCP requests or responses, you need to enable the rewrite feature on the Citrix ADC appliance.

After enabling the rewrite feature, you need to configure one or more actions unless a built-in rewrite action is sufficient.

After you create any needed rewrite action(s), you must create at least one rewrite policy to select the requests that you want the Citrix ADC appliance to rewrite. A rewrite policy consists of a rule, which itself consists of one or more expressions, and an associated action that is performed if a request or response matches the rule.

If you want to build a more complex policy structure than is supported by single policies, you can create policy labels and then bind them as you would policies. A policy label is a user-defined point to which policies are bound. When a policy label is invoked, all the policies bound to it are evaluated in the order of the priority you configured. A policy label can include one or multiple policies, each of which can be assigned its own result. A match on one policy in the policy label can result in proceeding to the next policy, invoking a different policy label or appropriate resource, or an immediate end to policy evaluation and the return of control to the policy that invoked the policy label.

When a request or response matches a policy in a policy label, administrators need to be notified. This way, they can figure out how effective or not a policy label is. This is exactly what the Rewrite Policy Label test does! This test auto-discovers the rewrite policy labels that have been configured on an ADC appliance and reports the count of requests/responses that match one/more policies in each label. In the process, administrators can identify the most- and least-effective policy labels. A closer look at the seldom-invoked labels may point you to inconsistencies in policy configuration.

Target of the test : A Citrix ADC VPX/MPX

Agent deploying the test : A remote agent

Outputs of the test : One set of results for each rewrite policy label configured on the Citrix ADC VPX/MPX appliance being monitored.

Configurable parameters for the test
Parameter Description

Test Period

How often should the test be executed.

Host

The IP address of the host for which the test is being configured.

NetScaler Username, NetScaler Password, and Confirm Password

To monitor a NetScaler device, the eG agent should be configured with the credentials of a user with read-only privileges to the target NetScaler device. Specify the credentials of such a user in the NetScaler Username and NetScaler Password text boxes. Then, confirm the password by retyping it in the Confirm Password text box.

SSL

The eG agent collects performance metrics by invoking NITRO (NetScaler Interface Through Restful interfaces and Objects) APIs on the target NetScaler device. Typically, the NITRO APIs can be invoked through the HTTP or the HTTPS mode. By default, the eG agent invokes the NITRO APIs using the HTTPS mode. This is why, the SSL flag is set to Yes by default. If the target NetScaler device is not SSL-enabled, then the NITRO APIs can be accessed through the HTTP mode only. In this case, set the SSL flag to No.

Measurements made by the test
Measurement Description Measurement Unit Interpretation

Policy label hits

Indicates the number of requests/responses in the last measurement period that matched one/more policies in this policy label.

Number

Compare the value of this measure across labels to know which label is invoked the most and which is not. Scrutinizing the least-used labels may throw some light on what could be ailing them.