Radware Alteon, Инструкция по применению

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Alteon Application Switch Operating System Application Guide
Server Load Balancing
202
Document ID: RDWR-ALOS-V2900_AG1302
Assigning Multiple IP Addresses
One way to provide both SLB access and direct access to a real server is to assign multiple IP
addresses to the real server. For example, one IP address could be established exclusively for SLB
and another could be used for direct access needs.
Using Proxy IP Addresses
Proxy IP (PIP) addresses are used primarily to eliminate SLB topology restrictions in complex
networks (see
Client Network Address Translation (Proxy IP), page 190 ). PIP addresses can also
provide direct access to real servers.
If Alteon is configured with proxy IP addresses and the client port is enabled for proxy, the client can
access each real server directly using the real server's IP address. To directly access a real server,
the port connected to the real server must have server processing disabled. However, if DAM is
enabled (
/cfg/slb/adv/direct ena
), server processing must be enabled on the server port
regardless of the proxy setting and SLB is still accessed using the virtual server IP address.
Mapping Ports for Multiple IP Addresses
When SLB is used without PIP addresses and without DAM, Alteon must process the server-to-client
responses. If a client were to access the real server IP address and port directly, bypassing client
processing, the server-to-client response could be mishandled by SLB processing as it returns
through Alteon, with the real server IP address getting remapped back to the virtual server IP
address on Alteon.
First, two port processes must be executed on the real server. One real server port handles the
direct traffic, and the other handles SLB traffic. Then, the virtual server port on Alteon must be
mapped to the proper real server port.
Figure 34 - Mapped and Non-Mapped Server Access, page 202 illustrates a topology where clients
can access SLB services through well-known TCP port 80 at the virtual server's IP address. Alteon
behaves like a virtual server that is mapped to TCP port 8000 on the real server. For direct access
that bypasses the virtual server and SLB, clients can specify well-known TCP port 80 as the real
server's IP address.
Figure 34: Mapped and Non-Mapped Server Access
Port mapping is supported with DAM when filtering is enabled, a proxy IP address is configured, or
URL parsing is enabled on any port.