Introducing Redundancy at First point of Contact

[ehskaga]

Currently Load balancing of web components (at web container level) for jboss are served by external hardware load balancer or through the web server proxy (e.g mod_jk for Apache). This also helps in introducing redundancy (which directly means better availability) at web container level.

What is the strategy to have this redundancy at the web server i.e. single DNS being represented by multiple machines, else the web server becomes a single point of failure in a clustered environment. One way is to have external hardware load balancer taking care of it (which also would need to have redundancy) but i was more interested in the software options (which are cheaper in nature). One option that i could think of is the Network Load balancing component available with the Windows server but that has the drawback of being properiatory as well as would not support the session stickiness in case application is stateful at HTTP level.

[brian.stansberry]

A possibility is to use Heartbeat on the web server:

http://www.linux-ha.org/

http://www.linux-ha.org/HeartbeatProgram

This page has a better explanation of what Heartbeat does:

http://www.ultramonkey.org/2.0.1/heartbeat.html

[ehskaga]

If i have understood the concept correctly, it would make the system dependent on linux as an OS. I mean it is the same as the NLB component availble in indows 2000 server which mwakes the system Windows dependent.
Does this mean that this requirement can be met by OS specific components. Isn't there a OS independent compoenent/strategy available to achieve the same.

Kindly, correct me if i am wrong.

[brian.stansberry]

I'm not aware of anything that's both 1) software based and 2) OS independent.