Alteon Application Switch Operating System Application Guide
Global Server Load Balancing
742
Document
ID:
RDWR-ALOS-V2900_AG1302
11. Configure a static entry for client network 20.0.0.0.
Configuring Dynamic Client Proximity
To configure dynamic client proximity for all sites according to the example, follow the procedure for
Configuring Static Client Proximity, page 735
, leaving out
.
For configuring the sites, see:
•
•
•
For the example, when Client X loads the browser and enters the URL www.radware.com/products/
index.html, the system sends a DNS getHostByname query to the client's local DNS server for the
www.radware.com IP address.
Workflow for GSLB Dynamic Client Proximity
The following is the workflow for the example as shown
Figure 125 - GSLB Client Proximity Site with
using HTTP-based dynamic client proximity:
1. The Client X DNS requests the local DNS server to send the www.radware.com IP address.
2. The local DNS server queries the upstream DNS server on Alteon.
3. The Site A Alteon receives a DNS request and acts as the authoritative DNS. Site A responds to
the DNS request with a Site A VIP address according to the DNS GSLB configured metric.
4. The client opens an HTTP application session with Alteon at Site A.
5. Site A receives the HTTP request and checks the client proximity entry. If a client proximity entry
does not exist, computation begins for this client network.
6. Alteon at Site A responds with three URL links. The Site A Alteon computes multi trip time (RTT)
with the client from current connection and obtains remote site's RTT through DSSP updates.
The following are the URL links at Site A:
—
http://<Site A IP address>/products/index.html
—
http://<Site B IP address>/radware_client_proximity_url
—
http://<Site C IP address>/radware_client_proximity_url
7. Client X sends an HTTP request to Site A, Site B, and Site C. Client X establishes a TCP
connection with Site B and Site C, and sends a cntpurl request. Site B and C respond with a
dummy response and in the process compute the RTT of their TCP connections with the Client X.
Site B and Site C update the computed RTTs to Site A. On receiving RTT from Sites B and C, Site
A sends the consolidated RTT list to all sites.
8. At this time, Site A serves the request from the client.
9. During the next request from the Client X, Site A redirects the HTTP request to the closest RTT
Site (Site C in this example).
10. Client X opens a new connection with Site C.
>> # /cfg/slb/gslb/network 3
ena
sip 20.1.1.10
mask 255.0.0.0
addvirt 1 10
addreal 2 20
addreal 3 30
(Most preferred site)
(Least preferred site)