Manual Chapter :
Redirecting DNS Queries Using a CNAME Pool
Applies To:
Show Versions
BIG-IP LTM
- 17.0.0, 16.1.5, 16.1.4, 16.1.2, 16.1.1, 16.1.0, 16.0.1, 16.0.0
BIG-IP DNS
- 17.0.0, 16.1.5, 16.1.4, 16.1.2, 16.1.1, 16.1.0, 16.0.1, 16.0.0
Redirecting DNS Queries Using a CNAME Pool
Overview: Redirecting DNS queries using a CNAME pool
When you want to redirect DNS queries for a web site to a different web site, create a wide IP
that represents the original web site, and add a pool configured with a CNAME type to the wide IP
with an A record type to redirect the requests to the new destination.
The executives at
siterequest.com
recently purchased a competitor.
Site Request's administrator wants to redirect DNS queries for
competitor.com
to a rebranded web site named
competitor.siterequest.com
. About CNAME
records
A
CNAME
record specifies that a domain
name is an alias of another domain. When you create a CNAME pool with members specifying the
canonical name, BIG-IP DNS responds to DNS name
resolution requests for A or CNAME name record type queries with these names if this pool is
added to the said wide IP.Creating a CNAME pool
Create a CNAME pool to which the system can load balance DNS queries. For example,
you can name the pool
competitor_redirect
and use a pool member
name of competitor.siterequest.com
. - On the Main tab, click .The Pool List screen opens.
- ClickCreate.The New Pool screen opens.
- In theNamefield, type a name for the pool.Names must begin with a letter, and can contain only letters, numbers, and the underscore (_) character.The pool name is limited to 63 characters.
- From theTypelist, select theCNAMEtype.
- In the Members area, for theMember Listsetting, from theWide IPlist, select either a pool member (A or AAAA type) or a static target, and then clickAdd.
- ClickFinished.
Creating a wide IP with a CNAME pool
Ensure that a pool configured with a CNAME type exists in the BIG-IP configuration.
Create a wide IP that includes a pool configured with a CNAME to redirect DNS
queries from a web site, to a different web site.
- On the Main tab, click .The Wide IP List screen opens.
- ClickCreate.
- In theNamefield, type a name for the wide IP.You can use two different wildcard characters in the wide IP name: asterisk (*) to represent several characters and question mark (?) to represent a single character. This reduces the number of aliases you have to add to the configuration.
- From theTypelist, select a record type to serve from the required DNS query types.If you want the BIG-IPDNS to respond to both A and CNAME record type requests, you must configure two wide IPs. One wide IP of type A with a CNAME pool type, and a second wide IP of type CNAME with a CNAME pool type. At a minimum, an A record type wide IP should be configured with a CNAME pool.
- In the Pools area, for thePool Listsetting, from thePoollist, select the name of the CNAME pool, and then clickAdd.
- ClickFinished.
Viewing statistics for wide IP CNAME resolutions
Ensure that a wide IP that includes a pool configured with a CNAME exists in the BIG-IP configuration.
You can view the number of DNS queries that BIG-IP DNS
(formerly GTM) resolved using a CNAME record.
- On the Main tab, click .The Global Traffic statistics screen opens.
- From theStatistics Typelist, selectWide IPs.Information displays about the cumulative number of DNS name resolution requests processed by the wide IP, and the number of requests load balanced using specific methods.
