[OpenAFS] AFS and XEN Virtualization

[Dr A V Le Blanc]

On Mon 2007-Jul-09, Jeff Greer <j.greer@oclcpica.org> wrote:
> I am in the process of researching migration from windows serves to 
> Linux. Currently my windows servers use DFS. I want to know if the 
> following will work.
> 
> 2 replicating failover AFS servers
> 10 Fedora Core - AFS Client - web servers
> 
> I would also like to make the AFS servers double as virtualization 
> servers for low traffic network services like mail, ftp and low traffic 
> webs. The remaining 10 web servers would get their web files and 
> Tomcat/Apache/Java installations from the pair of AFS servers.
> 
> The web applications are caching so once a disk file is read in it is 
> cached until the application is restarted. This should help reduce the 
> network traffic.
> 
> All servers would have bonded GIG ethernet.
> 
> I am planning my AFS servers to use the following hardware
> Dual Core AMD Opteron 2216, 2x1MB Cache, 2.4 GHz, 1 GHz HyperTransport
> 8 GIG memory
> Dual GIG Ethernet NICs
> 
> My question is this...can AFS and Xen coexist on the same machine well?

We have been running well with a similar setup for over a year.  We have
Dell PowerEdge servers running Xen (under Debian etch), and three of
the virtual hosts are the three AFS database servers.  We have 16
virtual hosts running our web services (8 for apache 1, and 8 for
apache 2), clustered using LVS and maintained using keepalived.
The LVS directors are also virtual hosts on the xen servers.  We
are not using Xen for AFS file servers; these are all standalone
machines.  I should say we have over 40 other virtual hosts doing
various jobs.  AFS clients and database servers seem to run well
on xen virtual hosts, though I have had some problems with test
kernels, which I simply did not roll out to production machines.

     -- Owen