web site failover - suggestions?

[David Rodman]

I'm looking for mechanisms to automatically failover a website to another hpux system. I know I can do it with mc-serviceguard, or third party hardware, other low tech suggestions are welcome...

For example: What can be done with sharing a virtual IP between two systems?

[Bill Hassell]

There are a number of blackbox and software tools to perform failover although it may make sense to look at load balancing boxes first. The adavantage is that a load balancer will handle the loss of one or more servers automatically.

These are now network appliances but be sure to look at the caveats on web design! Some web designs are not easily shareable or balanced without sophisticated backends. Static web pages are easy, whereas query and submission pages are more difficult.

And from a reliability point of view, be sure to look at the total package: LAN redundncy, switch redundancy, load balancing, query source redundancy, and so on. Every step of a web page's life should be traced to the hardware involved and reliability designed in accordingly.

[harry d brown jr]

Get a cisco content switch.

live free or die
harry

[Christopher Caldwell · Accepted solution]

Well, you can try things like nfs mounts for "virtual" IPs. We use the nfs clients as front ends to the nfs server (where the actually site storage is).

When you boil it all down, though, you'll need something that deals with shared storage over a shared architecture and something that deals with arp table and IP configs--that's MC/Service Guard.

You can deal with the shared storage with commands. Getting something to fail the IPs and update all the arp table entries on the network is a little more tricky.

You can try ifconfig lan a:n down, but I've never been able to get that to work very cleanly.

ServiceGuard does it cleanly.

[Christopher Caldwell]

P.S. I agree with the earlier posters - for performance and failure at the front-end, you need a switching appliance - but I'd still use something on the back-end as well.

[Derek McCutcheon]

Alteon web switches