I made some searches here and didn't find anything relevant enough for me. I'll try to be as brief as I can.
I currently have OSX servers, three of them. I am moving to a virtualisation enviroment for redundancy and since Apple has cancelled the Xserve. I have no prior experience with virtualisation, but I'm a quick learner and I have administered servers since 1997.
So, new dedicated server in new data center. Kickass hardware, installed VMware ESXi and inside that, I've created two networks, "VM Network" and "Switch". "VM Network" is connected to the physical NIC and "Switch" is a virtual switch.
Then I created a VPS named "FW" that has two virtual NIC's, one to each network in VMware, installed pfSense on this virtual machine and bridged the "real" NIC with the internal Switch. Done.
Then I intend to create my resource pool on the "Switch" network and let pfSense load balance it.
My Web application is currently contained in a single directory that weighs in at approx 300GB of data, my database is about 50GB more. They are currently on Xserve 1 and Xserve 2.
My current thought process has me at these VPS machines:
1. Main server (10.0.0.10) This contains two virtual hard drives, one small for Linux and one large for my web application. The larger is mounted inside Linux as "/Atlas" (name of my CMS) and is then NFS exported. VPS has 2GB of RAM and 2 CPU's
2. Database server (10.0.0.11) This is the master database server
3. Web servers (10.0.0.20 - 10.0.0.30) Ten Linux servers, each with 5GB of HD, 5GB of RAM and 4 CPU's. Each mount the NFS export from #1 and can read and write to my Atlas.
My questions are:
Should I run MySQL slaves on each Web server in 3? I only have about ~900GB in the server, so space is a concern.
If not, should I have seperate MySQL slave failover servers in the same VMware, in case something happens with #2?
I will rsync-backup the Main server to an offsite location, but is there a better way than NFS to let every web server read and write to this data. Using a cluster filesystem would lead to space concerns, rigth?
Should I use a VPS for load balancing and use Apache's own LB? Is that better for a web application than using pfSense's LB?
Any other weak points in my thoughts here? I will use this as my main server, but I will have a failover server set up identically in another location and use DNS servers to reroute the traffic when needed (either automatically or manually).
I'm not building the Fort Knox here, but I need better redundancy than I have today, and I want to do it as "correct" as possible. Any help/comments are greatly appriciated!