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Catalyst 6000 Family Software Configuration Guide—Releases 6.3 and 6.4
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Chapter 42 Configuring ASLB
Configuring ASLB
ASLB Configuration Guidelines
This section lists the usage guidelines and restrictions for configuring ASLB:
•
Routers, page 42-8
•
Servers, page 42-8
•
IP Addresses, page 42-9
•
Supervisor Engine, page 42-9
•
Backup LocalDirector Configuration (Optional), page 42-9
•
MSFC and Multilayer Switching, page 42-10
•
NetFlow Data Export, page 42-10
•
VLANs, page 42-10
•
Switch Port Configuration, page 42-10
For configuration examples, see the
“ASLB Configuration Example” section on page 42-19
. If you run
into problems during your configuration, see the
“Troubleshooting the ASLB Configuration” section on
page 42-25
.
Routers
Follow these router configuration guidelines:
•
The router must be the default gateway for the servers being load balanced and its MAC address
must be known.
•
Multiple routers must be on the same router VLAN. Specify all the participating router MAC
addresses using the
set lda mac router
command.
•
When ASLB is configured, a VACL is created to redirect TCP traffic on the two VLANs that the
LocalDirector is connected to; no security IOS ACLs or VACLs can be configured on these VLANs.
Servers
Follow these server configuration guidelines:
•
The servers must be either directly attached to the switch or within the same bridging domain as the
LocalDirector port in the server VLAN.
•
Configure the servers to ignore ARP requests for the virtual-IP address.
•
Configure the server default route as the aliased address of the router that is on the same subnet as
the real IP address of the server.
Caution
To accelerate traffic in the client to server direction, you must configure the servers to ignore ARP
requests for the virtual-IP address. If you fail to do this step, traffic acceleration will not start, and
fully redundant topologies in your network will take a long time to recover from a LocalDirector
failure.
•
On some server operating systems you cannot disable responses to ARP requests on alias
(secondary) IP addresses. Use static ARP entries at the routers as a workaround for the servers that
respond to ARP requests for the virtual-IP address.