Serving > Front Ends > Filters

Use the Serving > Front Ends > Filters page to restrict users' searches by front end, using filters for:

• Domain - restrict searches to one or more domain names (not IP addresses)
• Language - restrict searches to either all languages or a selected set of languages
• File type - restrict searches to one or more file types, such as HTML, PDF, and so on
• Query expansion - determine the extent to which queries are expanded with synonyms
• Result biasing - influence the way that the search appliance ranks documents as relevant to a user's search query
• Meta tags - filter searches by values and value types in meta tags

To use filters:

1. Click Serving and then click Front Ends.
2. Click the Edit link next to the front end you want to edit.
3. Click the Filters tab.
   From this page you can set up filters for the selected front end.

Domain Filters

When filtering by a domain name, all domains ending with that name are filtered. For example, the domain yourdomainname.com returns search results in all domains such as these:

www.yourdomainname.com
news.yourdomainname.com
ops.yourdomainname.com

However, if the domain name is followed by a directory name, the domain name must be fully qualified. For example, yourdomainname.com/marketing will not return any results under the domain name filter alone. The correct filter would be www.yourdomainname.com/marketing. If the directory marketing is in multiple domains, each filter must be specified individually -- one per line, one for each domain, such as these:

www.yourdomainname.com/marketing
news.yourdomainname.com/marketing

To set up a domain filter:

1. In the Domain Filter text box, enter at least one domain to which searches (using this front end) will be restricted to.
2. Press Enter to add another domain name so that each domain is on a separate line.
3. To make filter changes to another front end, click the down arrow in the Edit Front End drop-down menu and select the front end you want.
4. When finished, click the Update Filter button.

Language Filters

You can select, for any front end, to search for pages in any language or to search for pages in selected languages.

To set up a language filter:

1. In the Language Filter area, select either one of two options:
   Search for pages written in any language.
   or
   Search only for pages written in these language(s):
2. If you select the second option, select the checkboxes next to the languages you want to restrict search results to.
3. To make filter changes to another front end, click the down arrow in the Edit Front End drop-down menu and select the front end you want.
4. When finished, click the Update Filter button.

File Type Filters

The search appliance can crawl many file types.

Specify extensions without the leading period. Separate multiple extensions with spaces, NOT with commas. For example, the following extensions are correct:

pdf
pdf html xml

And the following extensions are incorrect:

.pdf
.xml .html
pdf, html, xml

To set up a file type filter:

1. In the File Type Filter text box, enter the extensions of file types to which you want to restrict the search results. For example, to restrict results to only HTML files, you would enter HTML.
2. To make filter changes to another front end, click the down arrow in the Edit Front End drop-down menu and select the front end you want.
3. When finished, click the Update Filter button.

Query Expansion Policy

Use the query expansion policy to provide a richer set of results in response to user search queries. Query expansion lets the appliance add synonyms to a search query that a user has entered.

You can use the built-in set of synonyms, or provide your own, or use the built-in terms and your own

To set the query expansion policy:

1. In the Query Expansion text box, select one of the following values:
   • None: Disables query expansion.
   • Standard: Enables query expansion, using the built-in synonyms.
   • Local: Enables query expansion, using only the synonyms that you upload to the appliance.
   • Full: Enables query expansion, using the built-in synonyms and the files that you upload to the appliance.
2. Click the Update Filter button.

If you use Local or Full query expansion, you can also use a blacklist to block expansion of specified terms.

Result Biasing

Result biasing lets you influence the order of documents on the search results page by applying adjustments to the scoring calculation. To set result biasing options, use the Serving > Result Biasing page. After setting result biasing options for a search appliance, you can enable result biasing.

To enable result biasing:

1. In the Result Biasing area, select Enable.
2. Click the Update Filter button.

To disable result biasing:

1. In the Result Biasing area, select Disable.
2. Click the Update Filter button.

Meta Tag Filters

You can filter search results by meta tag, restricting by "all" or "any," by value type, and by value.

To set up a meta tag filter:

1. In the Meta Tag Filter area, select one of the following options:
   • Match all
   • Match any
2. Enter the Meta Tag Name, such as "author".
3. Select the Value Type (Exact, Partial, Existence). For more information about value types, refer to the following section, Value Type Input Parameters.
4. Enter the Meta Tag Value, such as "Peter Norton".
5. To make filter changes to another front end, click the down arrow in the Edit Front End drop-down menu, and then select the front end you want.
6. When finished, click the Update Filter button.

Value Type Input Parameters

You can also filter results by the values of the results' meta tags using the requiredfields and partialfields input parameters in a search query. For information about these input parameters, refer to Search Protocol Reference on the public search appliance documentation page.

If you set meta tag filters in the front end (using the Meta Tag Filter area), the search appliance appends these settings to the search query as requiredfields and partialfields input parameters. If you set meta tag filters in both the front end and in requiredfields and partialfields input parameters, the front end settings overwrite any input parameters that you have added to the search query.

The following table lists front end meta tag value types and the input parameters that the search appliance appends to the search request for each value type.

Front End Value Type	Input Parameter
Exact	requiredfields=name:value
Partial	partialfields=name:value
Existence	requiredfields=name