Here are some things that I learned while setting up my VPS.
Make sure you have swap space I’m using Digital Ocean, and they have “droplets” which are pretty much just a empty install of some distribution of Linux to start with. They’re super easy and were a real breeze to set up. The last time I set up a Linux install on a local computer I made sure that either I manually created or the install tools made a swap partition. Droplets don’t come with swap partitions and it slipped my mind. Because of that I spent a surprisingly large amount of time trying to figure out why things kept complaining about low memory. Then I just made a swap file (which took me all of about 2 minutes) and things were great. The guide I linked to is a good resource for you if you don’t know how to do it. The guide makes a 64mb swap file. I made mine a half gig.
MX records have to have a dot after the TLD DNS record management is something I’m new at, so when I set up my MX record, I didn’t know the TLD is supposed to have a dot after it, and I’m not sure why that’s something that needs to happen, to be honest with you. Everything else I’ve ever worked with says the TLD stops at the .com or .net, and that’s that. If you’re setting up your own DNS records use an auditing tool like www.dnsstuff.com. It was a real help to me.
Distributions Change Strangely dig and nslookup don’t come standard with CentOS 6.3. At least not in the droplet provided by Digital Ocean. Those seem like standard tools for me, and I found it strange I had to install them by hand.