On Tue, Dec 16, 2008 at 1:58 AM, Alex Kovalyov <[email protected]>wrote:
> > > That would be great if that was how it always worked. It is true that > some, > > most, modern browsers will attempt to try the second/n address after > > attempting to connect for a few seconds. Unfortunately there are other > > issues like DNS caching, proxies, mobile browser etc that either don't > > support or disrupt the IP failover. In these cases it will resolve to the > > first IP, if that fails then it will just error out. > > AFAIK, browsers just make a sys call to OS-level DNS resolver, so that does > not really depends on how modern your browser is. Multiple A records is a > core part of DNS. Right, it is based on the network layer in the software... not necessarily the OS level thing. So just looking for a solution if one of the machines in the multiple-ip A record goes down. It's sounding like there isn't a standard way to deal with this in Scalr. > > Caching DNS servers must respect TTL values and refresh cache accordingly. > > > > > The round-robin does help with failover, but is more to distribute load > to > > clustered applications. This is part of the reason for floating IP's. If > a > > server fails then a different server can take over the IP and inherit the > > load that would be sent to the server from the round robin. > > > > That being said, I was hoping that people who use scalr had best > practices > > or possibly Scalr has some IP take over "magic" for servers that go down. > I > > know that an Elastic IP can be set to a server role and then reassigned > to a > > new instance that is replacing a failed one. This might be good enough if > it > > comes up fast enough... just looking for some tips. > > Instance starts to respond on elastic IP after 30 seconds to 5 minutes > after > it was assigned. This is a key problem. I'll start playing with some options. I'm thinking it might be fine to just go with Scalr's standard response time you described below for now. Thanks > > > > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "scalr-discuss" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/scalr-discuss?hl=en -~----------~----~----~----~------~----~------~--~---
