ZyXEL Communications 2WG 434

Chapter 21 DNS

Figure 267 ADVANCED > DNS > Cache

The following table describes the labels in this screen.

Table 140 ADVANCED > DNS > Cache

LABEL	DESCRIPTION
DNS Cache Setup

Cache Positive DNS	Select the check box to record the positive DNS resolutions in the cache.
Resolutions	Caching positive DNS resolutions helps speed up the ZyWALL’s processing of
	commonly queried domain names and reduces the amount of traffic that the
	ZyWALL sends out to the WAN.

Maximum TTL	Type the maximum time to live (TTL) (60 to 3600 seconds). This sets how long
	the ZyWALL is to allow a positive resolution entry to remain in the DNS cache
	before discarding it.

Cache Negative	Caching negative DNS resolutions helps speed up the ZyWALL’s processing of
DNS Resolutions	commonly queried domain names (for which DNS resolution has failed) and
	reduces the amount of traffic that the ZyWALL sends out to the WAN.

Negative Cache	Type the time (60 to 3600 seconds) that the ZyWALL is to allow a negative
Period	resolution entry to remain in the DNS cache before discarding it.

Apply	Click Apply to save your changes back to the ZyWALL.

Reset	Click Reset to begin configuring this screen afresh.

DNS Cache Entry

Flush	Click this button to clear the cache manually. After you flush the cache, the
	ZyWALL must query the DNS servers again for any domain names that had
	been previously resolved.

Refresh	Click this button to reload the cache.

#	This is the index number of a record.

Cache Type	This displays whether the response for the DNS request is positive or negative.

Domain Name	This is the domain name of a host.