Ok, I say going HA/LB/GRID .. because depending on who you ask, you get the setup we deploying named after one of them.
I gave the guys the green light yesterday to go ahead and setup the load balancers, NFS and redundant servers for the Linux setup, we expect to have it al done, and tested in as little as 4 weeks, but it can be as much as 8.
This is a sketch on how the network will look (not all servers are listed, but gives a good idea)
High Availability doesn’t come cheap, but looks pretty 🙂
I am now in talks with the 3TERA folks about using Applogic with H-Sphere (as a PSoft executive, for PSoft clients and their H-Sphere setups), and I am VERY excited about it, and I believe it’s a terrific solution that our clients will love, but I wont be using it for Relio, for several reasons, none of them is me not trusting the technology, au contraire, I think it’s great, but mainly, I need to deploy this NOW .. and we still have a long road ahead before H-Sphere and Applogic and speaking to each other, second, for OUR kind of setup, I see a little bit of resource wasting with Applogic…
3TERA’s solution uses VPS’s for servers (nodes), it’s nice, and they can be deployed rather quickly .. but for Relio I see it as a waste of resources, if I put 10 VPS’s on 1 server, each VPS will consume allot of OS related resources, so I get less output from that server.
Instead what we doing is doing proper load balancing for HA .. by making each node a actual physical server .. now the downgrade is that it takes more time to deploy a hardware server, so if you are in the business of providing instant growth potential to clients, it’s slower than VPS (I can deploy a vps in minutes, a server .. 1 hour, if it’s in stock).
But thats not the market we are after, we instead wish to provide High Availability / Reliability .. so, as such, each server will have at least 2 nodes running at all times, if one goes down, the other is still alive and taking requests, this also allows for a sideways growth, were instead of deploying . say WEB10 .. you deploy another node on WEB9 .. so now WEB9 has 3 servers running, it can take allot more traffic.
Also, all the web data does not reside on the webservers, but on the NFS system instead, so when any of them goes down, the data itself is unaffected.
Our intention is to have each server (WEB) run on 3-4 nodes .. so if any of them breaks .. there are 2 or 3 left to take the load .. then you dont mind if it takes 1 hour to bring the problem node back up.
Also, another nice thing with the 3TERA solution, is the fact that it’s also easier to move your whole infrastructure to another provider if you need to do so in a harry, we are literally our own providers, so that also does not apply.
Back on our setup…, this also opens up another possibility, later when we have load balancing for Windows, if we make the data all reside on the NFS systems, we can focus in having single accounts for Linux and Windows .. each deployed domain would simply be assigned to one platform or the other.
I’m not sure yet how windows plays (if any) with NFS .. so more discussions on that will be needed with the dev team, but if I could have a single FTP to load up both my windows and linux domains .. that would be heaven 🙂