ZyWALL 5/35/70 Series User’s Guide

26.8 Configure DNS Cache

To configure your ZyWALL’s DNS caching, click ADVANCED, DNS, then the Cache tab. The screen appears as shown.

Figure 203 DNS Cache

The following table describes the labels in this screen.

Table 150 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.

 

 

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Chapter 26 DNS