Interesting approach. Let's take it offline and I'll send you more questions. ;) Thanks!
-- rick ----- Original Message ----- From: "Niclas Hedhman" <[EMAIL PROTECTED]> To: "General OPS4J" <general@lists.ops4j.org> Sent: Tuesday, September 25, 2007 1:25 AM Subject: Re: Need to deploy a gateway > On Tuesday 25 September 2007 11:49, Rick Litton wrote: >> My first concern is to ensure reliability by avoiding an SPF >> (single point of failure). Also, I'm not so >> sure that a single HttpService service bundle can do the job, i.e. it >> doesn't become a bottleneck. > > First, I would use a DNS trick. Set the up a a zone, where each redundant > GW > machine is the NS, and that the record for the GW to the client points > back > to the same machine. I would probably embed Apache Directory Server to > serve > that DNS zone (see below). > > Let's say; app.ops4j.org is the entry point of the system. The machine > app1, > app2, app3 are the redundant machine. The IP numbers of those are the > NameServers for the app.ops4j.org zone, and the @ entry in each machine is > listing itself. > > > This brings you; > 1. If a machine dies completely, the DNS client are required to try the > next > NS. So on DNS lookup, you will always get to a working machine. > > 2. Since Apache Directory Server sits in the same JVM, if the JVM dies the > DNS > goes down with it, and point 1 will apply. > > 3. Automatic load balancing of the clients to each of these machines. DNS > spec > states that the client must choose a NS at random. > > Secondly, I would try to cut out these machines from the loop of normal > requests if possible, so that long running sessions are going to fail due > to > crashes in this machines. The actual approach is of course very dependent > on > the requirements, the application type and other factors. > > > Thirdly, I would hire my team to do the job ;o) > > > Cheers > -- > Niclas Hedhman, Software Developer > > I live here; http://tinyurl.com/2qq9er > I work here; http://tinyurl.com/2ymelc > I relax here; http://tinyurl.com/2cgsug > > _______________________________________________ > general mailing list > general@lists.ops4j.org > http://lists.ops4j.org/mailman/listinfo/general _______________________________________________ general mailing list general@lists.ops4j.org http://lists.ops4j.org/mailman/listinfo/general
