Before you start, make sure that you have activated licenses for BIG-IP DNS, and both the CGNAT and DNS services.
You can create a custom DNS profile to configure
how the BIG-IP system handles DNS
queries.
-
On the Main tab, click or .
The DNS profile list screen
opens.
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Click Create.
The New DNS Profile screen
opens.
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In the Name field, type a unique
name for the profile.
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In the General Properties area, from the
Parent Profile
list, accept the default dns profile.
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Select the Custom check box.
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In the DNS Features area, from the GSLB list, accept the default
value Enabled.
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In the DNS Features area, from the DNS IPv6 to IPv4 list, select
how you want the system to handle IPv6 to IPv4 address mapping in DNS queries
and responses.
Option |
Description |
Disabled
|
The BIG-IP system does not map
IPv4 addresses to IPv6 addresses. |
Immediate
|
The BIG-IP system receives an
AAAA query and forwards the query to a DNS server. The BIG-IP system
then forwards the first good response from the DNS server to the client.
If the system receives an A response first, it appends a 96-bit prefix
to the record and forwards it to the client. If the system receives an
AAAA response first, it simply forwards the response to the client. The
system disregards the second response from the DNS server. |
Secondary
|
The BIG-IP system receives an
AAAA query and forwards the query to a DNS server. Only if the server
fails to return a response does the BIG-IP system send an A query. If
the BIG-IP system receives an A response, it appends a 96-bit
user-configured prefix to the record and forwards it to the client.
|
v4 Only
|
The BIG-IP system receives an
AAAA query, but forwards an A query to a DNS server. After receiving an
A response from the server, the BIG-IP system appends a 96-bit
user-configured prefix to the record and forwards it to the client.
Important: Select this option only if
you know that all your DNS servers are IPv4 only
servers.
|
If you selected Immediate, Secondary, or V4 Only two new fields
display.
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In the DNS Features area, in the IPv6 to IPv4 Prefix field,
specify the prefix the BIG-IP system appends to all A query responses to an IPv6
request.
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In the DNS Features area, from the IPv6 to IPv4 Additional Section
Rewrite list, select an option to allow improved network
efficiency for both Unicast and Multicast DNS-SD responses.
Option |
Description |
Disabled
|
The BIG-IP system does not
perform additional rewrite. |
v4 Only
|
The BIG-IP system accepts only
A records. The system appends the 96-bit user-configured prefix to a
record and returns an IPv6 response to the client. |
v6 Only
|
The BIG-IP system accepts only
AAAA records and returns an IPv6 response to the client. |
Any
|
The BIG-IP system accepts and
returns both A and AAAA records. If the DNS server returns an A record
in the Additional section of a DNS message, the BIG-IP system appends
the 96-bit user-configured prefix to the record and returns an IPv6
response to the client. |
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In the DNS Features area, from the Use BIND Server on BIG-IP
list, select Enabled.
Note: Enable this setting only when you want the system to
forward non-wide IP queries to the local BIND server on BIG-IP DNS.
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To have the BIG-IP system set the client subnet option to the query source
address for queries that do not already contain a client subnet option, from the
Insert Source Address into Client Subnet Option list,
select Enabled.
This also causes the BIG-IP system to remove the client subnet option from
responses to clients that did not send a client subnet option in their most
recent query.
Note: Enabling this setting prevents the configuration of a DNS
cache on the same DNS profile.
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Click Finished.