Very good points Donovan, that's certainly something to bear in mind, thanks for answering my question :-)
Richard. On Thursday, 3 January 2013 16:41:58 UTC, Donovan wrote: > > The problem is with DNS convergence it takes time when your lb fails. Even > if you have low ttls; If you use an eip you avoid that. > > I've had lb's fail and come back and still some people bacause of DNS > caching > at the browser and local resolvers unable to reach the site. I've never had > that issue when using eip's. Also when you use eip's you can make A records > to the root of your DNS zone safely. > > If you have other DNS not under scalr control you can use A records > instead of cnames which are faster to resolve. > > > On Jan 3, 2013, at 8:11 AM, RichBos <[email protected] <javascript:>> > wrote: > > Hi Donovan > > Interesting, I'm wondering why you would use an EIP as the nature of Scalr > DNS negates the need for such? It seems like an unnecessary step? > > That said, load (and/or instance size) isn't really a concern for us at > the design stage, we're just wondering if the Nginx LB is actually needed > for a multiple instance LAMP farm as even though the Sclar wiki advises > otherwise it's unclear how traffic would be distributed if not, unless, as > Srini states, there may be some low-latency round robin DNS baked into the > LAMP role? > > Richard. > > On Thursday, 3 January 2013 16:02:45 UTC, Donovan wrote: >> >> Use a nginx lb with an elastic ip; point dns to the elastic ip. I've >> found micros work fine for lbs even with https. Then I monitor. If the >> micro gets overloaded I skip smalls and go straight to c2.mediums. >> >> On Jan 3, 2013, at 6:54 AM, RichBos <[email protected]> wrote: >> >> Hi, I'm just wondering if an Nginx load balancer is required for a x2 >> role LAMP Farm? (As it would be using x2 App instances). I would expect so >> but the Wiki documentation says no. However as I understand it wouldn't the >> DNS be better pointed at the Nginx LB rather than the LAMP (app) 'role'? >> I'm only thinking so as if not how would (web/app) traffic be distributed >> evenly between the x2 LAMP instances? Or have I misunderstood things? >> >> http://wiki.scalr.com/display/docs/Mixed+images+-+LAMP >> >> Any advice appreciated. >> >> Richard. >> >> -- >> >> >> >> -- > > > > --
