Hi, I'm trying to use keepalived to create an HA setup for two web servers. I have 3 public IPs, a static for each node and a "shared" ip. The shared was created as a second IP for www1. I've set up the IP Failover linkage for both nodes in the Network tab of the management interface.

I have two questions:
1. How do I get www1 to respond using the new public ip? I created a virtual ethernet for it but it will doesn't respond to any requests. I also tried taking down the main IP and replacing it with the new one but it doesn't work. Any ideas?

2. Can anyone give me article links (or just some tips) on setting up keepalived for public IPs between two servers? I'm a bit confused how it all works. I'm using HAproxy to load balance, btw.

Thanks!!

Figured it out. I trolled the forum for a bit and found http://www.linode.com/forums/viewtopic.php?t=4946. Tried it and it worked. Also, set up keepalived using http://www.howtoforge.com/setting-up-a- ... n-lenny-p2 and hey, it "just works."

I never knew about the "ip address ..." command.

Keep in mind that since Linode's IP failover requires that both nodes be in the same datacenter, it's not really a HA setup since you have no geographic diversity. All you're protected from is host failures, not DC-wide issues (such as connectivity).

Thanks for the tip. Multiple datacenters isn't something I'm going to attempt just yet. I understand the benefits of it, but until we start getting real traffic from real customers, it doesn't make too much sense for us to double our hosting infrastructure. Also there's only so much I can do in a night...I'm learning all this scaling/HA stuff little-by-little as I go in my free time.

Out of curiosity, is the only way to do DC failover through DNS?

I believe so, since there's no IP failover.

Without using some form of global load balancing solutions, DNS is the only surefire way I can think of off the top of my head. And in theory, GLB just hacks up DNS to work in a way that provides the redundancy.