On essentially any current Linux distro, xs-tools doesn't actually install any drivers (in the days of RHEL4 and the like it used to have custom kernels as the vendor ones had severe limitations), because as you say the kernel has the support built in (PVops).
What xs-tools gives in Linux is: - Reporting of the VM distro etc back to the toolstack - In guest memory usage reporting back to the toolstack - Installs some userspace xenstore tools The XenServer toolstack does gate some VM operations on the presence of the tools, in particular migrate. This is somewhat historical (as the tools aren't doing any driver changes they don't actually affect whether the migrate would succeed or not, but when different kernels were required the presence of the agent gave an indication the correct kernel was in use, and it is shared code with Windows guests where you do need the drivers to migrate safely), and may be changed in future, but for now is a limitation. In terms of versions, we should ideally always install one from the latest XenServer release, these should (though I'll need to do some tests to be 100% sure) work on older ones as well with no problems. Older ones will likely work properly on newer versions as well, though it will in some cases cause an out of date warning to appear in XenCenter, which could be worrying for users. Alex ________________________________________ From: Pierre-Luc Dion [pd...@cloudops.com] Sent: 09 September 2014 17:59 To: dev@cloudstack.apache.org Subject: Re: [DISCUSS] How xs-tools gets installed for xen vms and systemvms Hi Ian, you are probably right about the PV driver of Debian 7, I can't confirmed. But, the xs-tools also provide interesting ressources usage metrics of VMs in XenServer. I think it is also required for xenmotion of VMs for maintenance purposes.
