Is there any advantage of using OpenVZ on a dedicated server for single-use?

Question

We are leasing a dedicated server where we plan to host an XMPP server. Currently, Debian is installed. Our current requirement is this will only be the production box; however, this could change if the production load is not using all the resources. I suppose we would be giving the one and only container all the resources day 1, though.

Is there any advantage or disadvantage of going ahead and installing OpenVZ from the start? Are there other unknown things we would have to contend with? For example, our box will likely have a high number of incoming connections. Would this have to be managed both on the host and container?

Thanks.

Answer 1

You get a few hours of down time if you decide to virtualize later. Not a very big deal since you can just have some other machine run the service during that time, or do it while nobody's expected to be logged in (night, weekend, holiday etc.).

The real question is, why on earth would you even consider OpenVZ? That will just add a layer of unnecessary complexity. Especially when there are real virtualization solutions available. In an OpenVZ container, your standard Unix tools (ps, top etc.) often will display incorrect information, and to find out what's really going on you have to read /proc/user_beancounters (and hope you interpreted it correctly; it's very non-standard). Not to mention your resources are not fully virtualized, so guests aren't 100% isolated. This means a misbehaving guest can have a significant negative impact on the rest of the server.