Add option to prefer the non-DNS resolves

Description

In addition to https://webarchive.jira.com/browse/HER-351, you should have an option to prefer using the non-DNS resolves and then falling back to the dns lookup.

Attached is a patch with the suggested changes to the FetchDNS class.

The new settings property is a boolean called preferNonDnsResolves for the FetchDNS fetcher.

This option would help when you are inside of an private network and want to crawl a server on your own network by its public name. In that case you would prefer to use the local hosts files to specify the private IP of the server.

Environment

None

Assignee

Unassigned

Reporter

Andres Aguilar

Labels

None

Issue Category

None

Group Assignee

None

ZendeskID

None

Estimated Difficulty

None

Actual Difficulty

None

Affects versions

Priority

Minor
Configure