Expiration Policies

As is the case with any system that enables end-user content to be contributed, considerations for expiring old data and removing it from the system should be implemented. Rules for removing content, called expiration policies, can be specified. Select the Expiration Policies node in the left pane of the MMC and the policies are listed in the right pane. When a new NNTP virtual server is created, expiration polices are not in place.

An expiration policy has the following properties:

• Expiration Policy Name Name of the policy that is displayed in the right pane of the MMC when the expiration policies are listed

• Newsgroups Affected List of wildcard characters and newsgroup names that will be used by the NNTP service to identify the newsgroups that should have the expiration policy applied

• Order Of Execution Multiple rules may be set for an NNTP virtual server so the order in which they are executed may be established

• Expiration Time Period The time period, in hours, for deleting the messages in the newsgroups that meet the criteria established in the expiration policy

New NNTP Expiration Policy Wizard

The New NNTP Expiration Policy Wizard is the only method available for creating a new expiration policy. Follow these steps:

1. In the MMC, right-click the Expiration Policies node and choose New | Expiration Policy to start the New NNTP Expiration Policy Wizard.

2. The wizard will prompt for the expiration policy name, which is displayed in the right pane of the MMC when the Expiration Policies node in the left pane of the MMC is selected. Click the Next button to continue.

3. You’re prompted for the newsgroups that are to be affected by this policy. Newsgroups may be added by clicking the Add button. Selecting a newsgroup from the list and clicking the Remove button will remove the newsgroup immediately—without a confirmation. The Move Up and Move Down buttons will determine the order in which the newsgroups will be processed. Click the Add button to open the Add Newsgroup window.

4. In the Add Newsgroup window, you can select the option to include or exclude the newsgroup specified in the Newsgroup text box. Enter a string in the Newsgroup text box that describes the newsgroup or newsgroups that should be affected. Newsgroups may also be specified using wildcard characters—specifying the * represents all of the newsgroups. Click OK to add the newsgroup to the Newsgroups Affected wizard screen and to dismiss the Add Newsgroup window.

5. When all of the newsgroups are added to the Newsgroups Affected screen of the wizard and the execution order is specified, click the Next button.

6. The final screen of the wizard prompts for expiration time period. Enter the number of hours after which articles should be removed from the newsgroup. The maximum time that may be set is 9999 hours. Then click the Finish button.

Configuring Expiration Policies

When the New NNTP Expiration Policy Wizard is used to make the expiration policy, the policy will be listed in the MMC when the Expiration Policies node is selected. After the policy is created, the NNTP virtual server applies it immediately to content. The NNTP virtual server will routinely parse the content with each expiration policy in the order in which it is set in the list of expiration polices. Various expiration policies may apply to the same message. The policy that the NNTP virtual server is enforcing at the moment the content meets the expiration policy’s qualifications will be removed before the next expiration policy is enforced. The expiration policy will cause the NNTP virtual server to take an action only after content is present in the newsgroup that qualifies based on the expiration policy’s properties. Any property in an expiration policy may be edited at any time by opening the Properties window for the policy and editing the following settings, as shown in Figure 5-8:

Figure 5-8: Expiration Policy Properties Window

• Remove Articles Older Than (Hours) Text box that contains the time in hours after which postings should be removed from the newsgroups affected.

• Newsgroups List of newsgroups that are affected by this policy. Use the Add, Remove, and Move Up and Move Down buttons to alter the policy.

As with newsgroups, expiration policies may be renamed, deleted, and refreshed. To perform any of these functions, right-click an expiration policy node in the right pane of the MMC and choose the appropriate action. Choosing to Rename an expiration policy will enable the name to be edited as it is displayed in the MMC. The Delete function deletes the expiration policy after you are presented with a confirmation prompt. The Refresh function will cause the MMC to query the NTPP service to get the latest configurations and expiration policy status to ensure that the expiration policy is displayed with the latest status in the MMC.