Brocade Communications Systems ServerIron ADX 12.4.00 - Manual (Page 37)

ServerIron ADX Global Server Load Balancing Guide 25
53-1002437-01
Proxy for DNS server
1
Syntax: host-info <host-name> alias <alias-name>
NOTE
Make sure you configure the alias only after configuring the zone and the host application the alias
is for, as shown in the example above. In addition, make sure you specify the fully-qualified name for
the alias (for example, “www.gslb.brocade.com” instead of “www.gslb”.
Configuring null host names
When you configure a zone name in GSLB, you enter the zone name, then associate host
applications with the zone name. For example, you might configure the following for the
“brocade.com” zone:
• www.brocade.com (HTTP application)
• ftp.brocade.com (FTP application)
Some e-commerce sites also accept just a zone name as an alias for a specific application within
that zone. For example, a site might accept both “www.brocade.com” and “brocade.com” as valid
names for the HTTP application on the web host. In this case, the second name has a null host
name. No application is explicitly associated with the “brocade.com” zone, but the DNS server is
configured to associate “brocade.com” with the same IP address(es) and application as
“www.brocade.com”, for example using address records or alias records.
NOTE
The real Authoritative DNS server must be configured to support Null Host.
To configure a null host name, enter commands such as the following:
ServerIronADX(config)# gslb dns brocade-name brocade.com

ServerIronADX(config-gslb-dns-brocade.com)# host-info www http

ServerIronADX(config-gslb-dns-brocade.com)# host-info null-host http
The last command in the example above configures a null host for the brocade.com zone and
associates the null host with HTTP.
Syntax: [no] host-info <host-name> | null-host <host-application> | <TCP/UDP-port-num>
You can configure one null host for each application and zone name.
Configuration example
Here is a proxy server configuration example for a GSLB ServerIron ADX.
To configure the ServerIron ADX as a DNS server proxy, enter commands such as the following:
ServerIronADX(config)# server real-name dns_ns 192.10.10.1

ServerIronADX(config-rs-dns_ns)# port dns proxy

ServerIronADX(config-rs-dns_ns)# exit

ServerIronADX(config)# server virtual-name-or-ip dns-proxy 192.10.10.69

ServerIronADX(config-vs-dns-proxy)# port dns

ServerIronADX(config-vs-dns-proxy)# bind dns dns_ns dns
The commands configure the GSLB ServerIron ADX as the proxy for the client’s DNS server.
The following commands configure the zone and host information for brocade.com and specify the
IP address of the proxy server.