3 ms·
For the webapp load balancing we do (which admittedly isn't very much; we're an ISP and aren't overly concerned with how quickly our homepage loads :p), we just
by frio 16y ago
For the webapp load balancing we do (which admittedly isn't very much; we're an ISP and aren't overly concerned with how quickly our homepage loads :p), we just use a DNS round-robin across a bunch of servers. We keep a short TTL so if a server dies, there's at most 5 minutes of downtime.
A better solution would be proxying, but we haven't had the need to step up to that: stick an nginx in front, put n backends behind it, and it'll distribute load across them as it sees fit. Of course, for reliability, you then need to drop a DNS round-robin on a couple of nginxes, so the whole thing repeats itself :).
But yeah, that's just for the frontend. For the backend databases, you'll want to look at replication and doing writes to one and reads from another, etc. We haven't had the need to do that, luckily :).
- whimsy 16y ago>we're an ISP and aren't overly concerned with how quickly our homepage loads Is this sarcasm?
- frio 16y agoNot at all. The priority has and will always be making sure customers can get to _other_ webpages quickly; we're not of a scale where the load on our own sales/account management pages exceeds the needs of 2-3 boxes (with a couple of redundant virtuals ready to fire up). That they feel fast to the CEO, without a defined metric for "fast", is about the only criteria.
- whimsy 16y agoThat's a great priority, and I applaud it. On the other hand, I'd have extreme apprehension of subscribing to any ISP with a webpage that loaded slowly - it would make me very concerned about their competence.
- cd34 16y agoBeing mindful of course of some of the larger broadband providers that ignore ttl<8 hours.
- slillibri 16y agoOne thing to keep in mind when using Round Robin DNS is that Microsoft is changing address selection with IPv6. 'DNS Round Robin and Destination IP address selection' http://blogs.technet.com/b/networking/archive/2009/04/17/dns-round-robin-and-destination-ip-address-selection.aspx http://blogs.technet.com/b/networking/archive/2009/04/17/dns... 'RFC3484' http://www.ietf.org/rfc/rfc3484.txt http://www.ietf.org/rfc/rfc3484.txt