This module provides the functionality to resolve domain names into IP addresses in an upstream at run-time.
Syntax: dynamic_resolve [fallback=stale|next|shutdown] [fail_timeout=time]
Enable dynamic DNS resolving functionality in an upstream.
The 'fallback' parameter specifies what action to take if a domain name can not be resolved into an IP address:
The 'fail_timeout' parameter specifies how long time tengine considers the DNS server as unavailiable if a DNS query fails for a server in the upstream. In this period of time, all requests comming will follow what 'fallback' specifies.