If the table in the Failover tab indicates that a server other than the primary server is “in use”, DNS records have been updated and failover has occurred. If you attempt to ping the host associated with the failover record and you still get the old IP, here are a few things to look at:
- What was the TTL value for the ‘A’ or ‘AAAA’ record that you assigned the failover pool to? We highly recommend making it 60 seconds. The higher your TTL the longer the old value will be cached around the world, particularly for people who just recently were connected.
- If the TTL was low or sufficient time has elapsed, you may need to clear your local cache. Some machines, like Windows, occasionally like to hang onto IP addresses longer than they should. To see if this is the case, open a command prompt (START > ACCESSORIES) and type in “ipconfig /flusndns” (without the quotes, of course). Now trying pinging the IP again.
- You may find it helpful to test using a third party external tool vs. your own machine. We like the tool at dnsquery.org. There you can query your specific ‘A’ or ‘AAAA’ record to see what the real value is right then and there. The nice thing about dnsquery.org is that they do not cache values at all. You can also use dnsstuff.com, they also have a free DNS traversal tool, but their site is no longer our favorite due to some terrible upgrades they made in the spring of 2012 that are still not fixed many months later.