Sorry for the convoluted title, I couldn't express myself properly in the character limit.

Basically, we've outgrown our little linode 512, and need to take the next step of keeping multiple server instances going. I was hoping someone could offer their advice or share their experiences as to what the better solution would be.

It looks as though if I choose to have a larger linode running multiple server instances, I'll need to purchase multiple IP addresses, where as purchasing individual linodes, they would all have their own IP address?

None of the websites in our portfolio are particularly heavy traffic and don't run anything much more intensive than multiple CMS installs. Our goal of keeping multiple linux instances running is more for security and partitioning our client base better.

Thank you in advance for any and all feedback.

If you need to keep the sites for each client separate for security reasons, then you haven't got much choice. However if it's just a would like if it's possible, then consider it carefully.

It all depends on what software you're running. Are we talking about a bunch of very light load PHP sites? Or instances of some software where adding another site requires a long running process to make sure response time is still good? Putting more sites onto a single server which is lightly loaded is probably better than wasting more resources, as you potentially need yet another instance with the same software on (Apache, MySQL, SSH, etc).

Another thing to consider is what software you're using. If you've got one bunch of sites running on one software package which is rather sensitive to server upgrades, multiple servers will give you the opportunity to change and upgrade the software on certain servers which need it whilst leaving other servers with fussy sites alone.

Then you've got the administration of multiple machines to deal with. Instead of upgrading one server with security updates, you've got to do it on each server. More experienced admins will be able to use tools like Puppet/Chef/cfengine to automate the deployment and maintenance of multiple servers, but I'm guessing this isn't something you've looked at if you only use a 512 Linode.

If you aren't forced to use multiple servers due to security requirements, given that you're using a 512 - I'd say upgrade that first and ask the question again later. But really more information would be great.

I don't exactly understand what you're asking. You don't have to have 1 site per ip address or Linode and it's a waste of resources if it's not needed. You also can't have more than 1 "server instance" running under each Linode at a time.

In other words, you don't need to have 2 nodes if you have 2 sites. 2 sites can easily run under the same node even assigned the same IP address. If this is for "security", then I'd suggest running some sort of chrooted environment so you can run multiple sites each under different accounts that can't access each other's files.

Hi Alex, thanks so much for your feedback.

We have a large chunk of small, mostly static php sites, a quickly growing list of Drupal sites, and a handful of important first party software we developed.

I really don't mind the administration of the multiple servers. I'm primarily a web developer, but I'm an advanced linux user ie: 'okay' administrator.

My question though has more to do with how I set up my linodes in particular. There are two ways it looks like I can go about this.

I can migrate to a bigger linode, then chop linode into multiple ubuntu servers,

or just spawn another linode with its own server.

Either way I would have multiple servers, But I get the impression that choosing one over the other will come with it's own set of configuration issues.

"You also can't have more than 1 "server instance" running under each Linode at a time. "

Well!

That changes everything! I was mistaken, and thought I could treat each linode as its own standalone virtual machine.

Thanks for the clarification!

I think there is some confusion in terminology here. Each node is a virtualized server, but they not virtual machines to run additional virtualized servers within. I suppose if you got a large enough node you could do that, but it's a huge waste of resources IMO.

You can boot a single Linux instance under any node at a time, but only a single one. So if each site is installed under it's on "linux instance" (configuration profile in Linode manager terms) you can only have 1 site running at a time.

Why do you think you need more than one linode? That's the ultimate question.

Do you need isolation between sites? A chroot jail type of solution can help with that. I have two copies of lighttpd running on my linode because one of my users wanted to run a phpbb3 forum, and I wanted to isolate that off a bit.

Do you just need to run multiple sites? Virtual hosting (or just different IPs) can accommodate that.

If you're running into load issues, I'd normally say to scale horizontally because it gives you redundancy (especially if you put the linodes in multiple datacenters), and it also forces you to solve the problems with horizontal scaling early on, when it's easier. But if you just need more RAM, or you just need to run more than one site or something, a single larger linode is easier.