Re: [tlug] Xen advice, please

[mcooper <mcooper@example.com>]

On Jan 10, 2007, at 4:57 PM, Curt Sampson wrote:

> I know people using Xen with production NetBSD systems; it works fine.
>
> You might want to think carefully about why you want to use it,  
> though.
> It essentially partitions your memory and disk space, so it reduces
> sharing of resources and makes resource planning harder. You'd have to
> a reason counterbalancing this to use Xen instead of just running more
> applications on a single server.

True. I was thinking that having all my servers virtualized would  
make management easier. I would be able to test things out buy just  
copying a virtual server and screwing it up irrevocably, etc. The  
freedom such an arrangement could afford is really seducing. It is  
more of a luxury, though. Our system is minimal, and the present  
setup is sufficient, so duplicating things as they are on new  
hardware would probably be easier and safer.

I have only one case that might necessitate a virtual server - our  
database intranet app. It is PHP4 on RHEL3, and it is built on an  
outdated version of a very early web framework (one of the very  
first, years before Rails) in which even the original developer is no  
longer interested. But we are heavily invested in it, difficult to  
maintain and modify though it is.

I thought that a virtual machine would be wonderful. If the present  
server can be replaced with a hosted vm, I can then copy the vm on  
the same host, test modifications before enacting them, and then make  
the same modifications on the app if there are no problems. But  
perhaps that is asking for luxury, too. I am sure that the test  
machine could be an old test box, for that matter, or a Parallels VM  
on a workstation.

I guess that, having researched it and listened to tluggers'  
opinions, it seems that I don't have an overwhelming reason to use  
Xen for production servers, since its maturity is still in question.  
The need does not justify the risk.

I would still like to hear more from Xen users, and if I am wrong  
about the above judgement, please tell me so.