This configuration parameter specifies the amount of time to wait, when DNS is active, before triggering a DNS server sweep to see if any DNS servers are responding faster than the current one.
The adclient process periodically checks in the background to see if any DNS servers are available with faster response times than the currently active DNS server. This parameter, dns.alive.resweep.interval, determines how often this check, or sweep, occurs. The default is one hour (3600 seconds).
For the sweep, the dns.sweep.pattern parameter determines the probe pattern that is used to find a live DNS server; that is, it sets:
- The protocol to use (TCP or UDP)
- The amount of time to wait for a response.
The DNS server that responds fastest is selected, is cached in memory, and is used for all DNS requests until one of the following occurs:
- It stops responding.
- A new server sweep discovers a faster DNS server and replaces it.
- Adclient is stopped and restarted.
If the newly selected server is different than the previous server, the kset.dns.server file is updated with the address of the newly selected server.
The default value for this parameter is 3600 seconds.
The parameter value must be a positive integer. For example: