Brocade Communications Systems ServerIron ADX 12.4.00 Manuale Utente

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ServerIron ADX Global Server Load Balancing Guide
53-1002437-01
Basic GSLB for IPv6 configuration
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The GSLB controller makes decisions based on the GSLB policy. In the example above, both the 
IPv6 VIPs were healthy, so client was directed to the IPv6 VIP that was geographically closer based 
on the configured policy. If the VIP at the geographically closer site (the US site) was down, the 
GSLB controller would direct traffic to the EU site.
1. US IPv6 client (browser) sends a DNS request for the website brocade.com.
2. The client’s local DNS server sends a recursive query for www.brocade.com to the GSLB 
controller (a ServerIron ADX with ADNS VIP).
3. The GSLB controller determines that the request is for an IPv6 address (query type AAAA) and 
so checks the IPv6 address list and identifies GSLB Site 1 (US) as the optimal IP for clients in 
the US based on the configured GSLB policy. (Similarly, a request for an IPv4 address would 
have been directed to GSLB Site 3 or Site 4.)
4. The GSLB controller sends a GSLB DNS response with the VIP address (2001:DB8::56) to the 
local DNS server. Note that the controller only sends the best IP to the querying client because 
"dns best-only" is configured in the GSLB policy. In the absence of this configuration, the GSLB 
controller would have sent back both IPv6 addresses with the best IP (2011:DB8::56) at the 
top of the response.
5. The local DNS server sends the GSLB DNS response to the querying client.
6. The US IPv6 client initiates communication with the selected VIP. Application traffic flows 
directly between the IPv6 client and the IPv6 VIP at GSLB Site 1.
Basic GSLB for IPv6 configuration
Basic configuration tasks include the configuration of the GSLB ServerIron ADX and the site 
ServerIron ADXs to support GSLB of IPv6 addresses. Tasks include the configuration of a VIP for the 
ADNS, the enabling and configuration of DNS cache proxy mode with override lists, and the 
definition of zones and sites on the GSLB ServerIron ADX. Also, the GSLB protocol must be enabled 
on the site ServerIron ADXs.
The features shown in 
 describe the configuration parameters required for a basic GSLB 
for IPv6 configuration.
TABLE 16
Basic GSLB for IPv6 configuration tasks 
Feature
See page...
On GSLB ServerIron ADX controller
Adding a VIP for the ADNS server
Enabling DNS cache proxy
Enabling DNS override
Specifying the zones and the host names within the zones
Specifying DNS override IP lists
Specifying the sites and the ServerIron ADXs within the sites
On Site ServerIron ADXs
Enabling the GSLB protocol