Brocade Communications Systems ServerIron ADX 12.4.00 - Manual (Page 114)

102 ServerIron ADX Global Server Load Balancing Guide
53-1002437-01
Enabling DNS request logging
1
For information about the statistics in the DNS cache proxy stat section, refer to “Displaying DNS
cache proxy statistics” on page 93.
Enabling DNS request logging
You can enable logging of the following information for DNS requests assisted by the GSLB
ServerIron ADX:
• Source IP address (the address of the client making the request)
• Best IP address (site address provided by the ServerIron ADX)
• Host
• Zone
• Metric used
When you enable logging of this information, the ServerIron ADX generates a syslog message for
each DNS requests assisted by the ServerIron ADX.
NOTE
The ServerIron ADX sends the log messages only to the external syslog servers you have configured
on the ServerIron ADX. The messages do not appear in the ServerIron ADX’s syslog buffer.
To enable logging of request information, enter the following command at the global CONFIG level
of the CLI.
ServerIronADX(config)# gslb log-dns
Syntax: [no] gslb log-dns
Here are some examples of the messages generated by this feature. In this example, client
1.1.1.21 sends four requests for www.gslb.com.
20:52:02 User.Info 1.1.1.102 GSLB DNS request: src-ip = 001.001.001.021 best-ip
= 001.001.001.101 Host = www Zone = gslb.com Metric = health-check
20:51:54 User.Info 1.1.1.102 GSLB DNS request: src-ip = 001.001.001.021 best-ip
= 001.001.001.101 Host = www Zone = gslb.com Metric = least-response
20:51:54 User.Info 1.1.1.102 GSLB DNS request: src-ip = 001.001.001.021 best-ip
= 001.001.001.023 Host = www Zone = gslb.com Metric = least-response
20:51:53 User.Info 1.1.1.102 GSLB DNS request: src-ip = 001.001.001.021 best-ip
= 001.001.001.022 Host = www Zone = gslb.com Metric = least-response
Each message shows the following information.
TABLE 7 Transparent DNS query intercept statistics
This field... Displays...
Redirect The number of queries the ServerIron ADX has redirected to an
alternative (proxy) DNS server or another ServerIron ADX.
Direct response The number of queries to which the ServerIron ADX has directly
responded using an IP address configured for the domain.