An application that is load balanced does not appear to work correctly when
running Windows NT Load Balancing Service (WLBS).
| • | All of the application's ports are not being load balanced. Some
applications require multiple ports to perform their functions. For
example, FTP uses ports 20 and 21. If both ports are not load balanced
(usually with one port rule), the application will not work correctly.
Check that the applicable port rule covers all ports used by the
application and be sure to enable client affinity (single or Class C).
|
| • | The application is not started on all cluster hosts. WLBS does not
start or control applications. You should check that the application has
been started on every cluster host. If an application fails, you can
disable its associated port range using the wlbs disable command.
|
| • | The application should not be load balanced. Applications that update a
file on the local cluster host may not work correctly when load balanced
because multiple instances of the application may conflict when
attempting to update a common file. For example, e-mail, groupware, and
database servers often have this problem. Do not load balance an
application until its data sharing requirements are thoroughly
understood and met.
|
| • | The application is not a TCP/IP service. WLBS load balances
applications by distributing incoming client requests among the cluster
hosts. If a server application is not structured as a TCP/IP service
that receives client requests, it will not benefit from using WLBS,
and you will not observe load balancing.
|
| • | Your firewall is proxying client traffic and making it appear as if all
connections are originating from the same client IP address. If the load
balancing rule is configured with Single affinity, all traffic will be
handled by the same cluster host. Turn off address translation
(proxying) on the firewall or change affinity from Single to None.
NOTE: You may need Single affinity to provide session support. |
Help and Support
Back to the top
