What kind of server do I need for a large forum?

[Vcize]

I recently started up a forum (don't worry, not a gay webmaster forum) that seems to be catching on pretty quickly. It just launched a few days ago and we've already got 2,000 posts and 600 members, and it's about a product that hasn't even been announced yet.

I spend most of my time with SEO stuff, and am a total n00b when it comes to server related stuff. Right now it is on a shared hosting account. Obviously, that's not going to last and I'd like to get it set up to handle a larger load before I end up with downtime for 100,000 members instead of 2,000.

However, I have no idea what I need. VPS? Full-on dedicated server? If the latter, how much ram, what kind of processor, etc am I looking at here?

At its height, I might expect around ~60-100 posts an hour or so, if it keeps growing at the rate it has so far.

Also, is there a way to make the switch without any downtime during the DNS propogation?

 

[Mahzkrieg]

I run a vBulletin forum with 200-350 concurrent users and over 4,000,000 posts (so, a medium sized forum). Was on an underwhelming Dreamhost VPS for almost three years until I had to pay more than $15/month.

Now I'm on a managed hybrid server (basically, a good VPS) with one CPU core and 4gb memory.

Forums are CPU intensive (and eventually I/O intensive), but it takes a while to get there. I recommend upgrading only when necessary.

And always tweak the software before you upgrade hardware. You'll be surprised how much longevity you can get out of a server that seemed capped after spending some time in the admin control panel. For example, there's no need to update a thread's view count instantly. Make sure shit's cached. Install a plugin that utilizes Memcache or Xcache. Reduce the global queries per pageload. Turn off things like the list of users that've logged in today. Store static media like avatars in the filesystem rather than the database.

Those are all toggle-on/toggle-off options in all of the main forum platforms.

Hardware-wise, the main thing you want is to be able to store the entire database in memory.