ZyXEL Communications USG110, User Manual

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Chapter 19 DNS Inbound LB
ZyWALL USG Series User’s Guide
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The following table describes the labels in this screen.
Table 168 Configuration > Network > DNS Inbound LB > Add/Edit
LABEL DESCRIPTION
Create New Object Use this to configure any new setting objects that you need to use in this screen.
General Settings
Enable Select this to enable this DNS load balancing rule.
DNS Setting
Query Domain Name Type up to 255 characters for a domain name for which you want the Zyxel Device to
manage DNS load balancing. You can use a wildcard (*) to let multiple domains match
the name. For example, use *.example.com to specify any domain name that ends with
“example.com” would match.
Time to Live Enter the number of seconds the Zyxel Device recommends DNS request hosts to keep
the DNS entry in their caches before removing it. Enter 0 to have the Zyxel Device not
recommend this so the DNS request hosts will follow their DNS server’s TTL setting.
Query From Setting
IP Address Select the name of an IP address object, including geographic address object, of a
computer or a DNS server which makes the DNS queries upon which to apply this rule.
DNS servers process client queries using recursion or iteration:
• In recursion, DNS servers make recursive queries on behalf of clients. So you have to
configure this field to the DNS server’s IP address when recursion is used.
• In iteration, a client asks the DNS server and expects the best and immediate answer
without the DNS server contacting other DNS servers. If the primary DNS server cannot
provide the best answer, the client makes iteration queries to other configured DNS
servers to resolve the name. You have to configure this field to the client’s IP address
when iteration is used.
Zone Select the zone of DNS query messages upon which to apply this rule.
Load Balancing
Member
Load Balancing
Algorithm Select a load balancing method to use from the drop-down list box.
Select Weighted Round Robin to balance the traffic load between interfaces based on
their respective weights. An interface with a larger weight gets more chances to transmit
traffic than an interface with a smaller weight. For example, if the weight ratio of wan1
and wan2 interfaces is 2:1, the Zyxel Device chooses wan1 for 2 sessions’ traffic and
wan2 for every session’s traffic in each round of 3 new sessions.
Select Least Connection to have the Zyxel Device choose the member interface which is
handling the least number of sessions.
Select Least Load - Outbound to have the Zyxel Device choose the member interface
which is handling the least amount of outgoing traffic.
Select Least Load - Inbound to have the Zyxel Device choose the member interface
which is handling the least amount of incoming traffic.
Select Least Load - Total to have the Zyxel Device choose the member interface which is
handling the least amount of outgoing and incoming traffic.
Failover IP Address Enter an alternate IP address with which the Zyxel Device will respond to a DNS query
message when the load balancing algorithm cannot find any available interface.
Add Click this to create a new member interface for this rule.
Edit Double-click an entry or select it and click Edit to open a screen where you can modify
the entry’s settings.
Remove To remove an entry, select it and click Remove . The Zyxel Device confirms you want to
remove it before doing so.
# This field displays the order in which the Zyxel Device checks this rule’s member
interfaces.