WordPress MU

I'm setting up a social network for international youth groups, and can expect some quite high traffic - especially when we start hosting photos and videos later in the year. We decided we would need a VPS for the flexibility it provides, and would be using Amazon S3 for storage anyway - so EC2 sounded great.

I'm extremely new to server administration, I dipped my toe in with SSH access with DreamHost for the past year, so managing a server myself will be quite a jump! This is the setup I've been thinking of:

* Linux distro (TBD)
* lighttpd 1.4.22
* PHP 5.2.9 + XCache or eAccelerator
* mySQL 5.1

And I'll probably run the current trunk versions of WPMU, BP and bbPress; unless I get any major problems with them.

What I'd like to know form anybody with server knowledge;

* What would be the best linux distro to use?
* Which is best for this, XCache or eAccelerator?
* I have an unused PC at home, if I installed linux on it and the above components, would it give me an adequate place to try things out? Effectively a staging server at home...?
* Any known caveats using Amazon EC2 and S3?

Cheers, it was WP that got me into PHP, so hopefully it can do the same for sysadmin stuff!

I've also been looking at the 'DB Cache' plugin, which I've heard is better that WP-Cache and WP Super Cache; is this true?

WP Super Cache is better when properly configured because it allows for the PHP engine to never be loaded for cached pages. You might be able to use them together as db cache might help for admin pages that WP Super Cache doesn't do.

As far as EC2, good luck! It can be very complex to set up, and it's instances are really designed to be temporary. You will have to worry about persistent storage too. I would'nt try EC2 until you are trying to create some kind of load balancer or dynamic process that spins up new servers as they are needed. I've been using slicehost to cut my teeth on linux server admin myself. Very flexible and they have great tutorials.

I'd have to go digging for the thread (and it's been months since we looked at it) but I believe the flash uploader within wp and wpmu require lighttpd 1.5 at least.

edit: http://redmine.lighttpd.net/issues/show/1017

reedit: Found my notes. Confirmed. It was for a VPS install we did last year. It'll install but you;re get an error with wordpress when you try the flash uploader that v1.5 is required. That error will be exposed to end users.

"I've also been looking at the 'DB Cache' plugin, which I've heard is better that WP-Cache and WP Super Cache; is this true? "

Actually, I just read that they cache different things, so you can use both.

Which makes sense, really...

Notes on EC2 and Amazon, it's a bit tricky, but it can be done. I've played around quite a bit with it. You would have to write a script to redeploy everything if your server goes down but basically you can start up a lamp instance, attach the EBS (elastic block storage) to it. Map you mysql to use the EBS storage to save it files. This way if the instance goes down all your DB info is saved. I've also been playing around with s3fs which will allow you to mount a amazon s3 bucket as a drive. I then create a sym link to that and keep all my wp-content on that mounted drive which transparently moves every thing to amazon s3.

I'm not using any of this in production however.

I want to check out DB caching... looks cool. DB's and bad sql are most of the time the biggest bottle neck.

We've got as box setup with nginx and it's miles better than Apache (so far).