Methodologies, strategies and experiences Virtualization

Methodologies, strategies and experiences

Virtualization

CANHEIT | Power Through Collaboration | May 27-30, 2007 | Virtualization - methodologies, strategies and experiences

Definition

the abstraction of computer resources

a technique for hiding the physical characteristics of computing resources from the way in which other systems, applications, or end users interact with those resources1

1 Enterprise Management Associates


Types and Players

Emulation - simulates complete hardware– Wine/Crossover

Hardware - simulates enough hardware– VMWare Workstation

Para-Virtualization - no hardware emulation, uses special API– Xen, VMWare ESX, User Mode Linux

OS-Virtualization - OS allows multiple secure virtual servers– Solaris Zones, BSD Jails, Linux-Vserver


Advantages

Consolidation (of course!)– Cost cutting via:

• People resources - arguable

• Hardware resources

Security - depends on type

Rapid reboot of virtual environment

Rapid deployment of another environment

Cloning - rapid test environment


Considerations

Shared memory - changes coming soonStorageThe kitchen sink effectPatch deployment / multiple versions– Positive or negative?

Many virtualization systems suffer from performance loss on some types of workloads (most loss found to be related to network and disk intensive tasks)– Solaris Zones does not suffer from this


Xen

Para-virtualization

Primarily modified Linux and NetBSD systems as host system

Support for various Linux and BSD, OpenSolaris, Netware as guests

Version 3.0 unmodified Windows ok(?)

Can run multiple guest operating systems

Commercial support available from XenSource

Full virtualization now available with new hardware

Can migrate live domains to new hosts


VMWare

Server (formerly GSX)– Para-virtualization, Windows/Linux host OS– Support for various guest OS– Can run multiple guest OS– Free! - but need to buy add-ons for some features

ESX– Full virtualization – Support for various guest OS– Can run multiple guest OS– Expensive ($5K+ for full version per physical system)


Solaris Zones

Operating system-level virtualization

Included with Solaris 10

Global zone vs Non-global zones– Global zone runs kernel– Global zone contains and used to administer non-global zones– Non-global zones can be given access to devices– Non-global zones cannot export filesystems via NFS

Non-global zones can be whole or sparse– Whole zones include own copy of all filesystems– Sparse zones share filesystems such as /usr with global zone– Sparse zones can take as little as 50-100MB


Architecture Considerations

Solaris zones setup as sparse to save on disk space

Patching installed globally to all zones

Each zone has /zones for local files


Where we are - Solaris Zones

All Solaris 10 servers setup with zones

Running on multiple hardware platforms

Global zone only used for server administration

All applications run on non-global zones

Zones setup as sparse zones

Largest implementation is on a T2000 with 8 non-global zones


Where we are - Xen/VMWare

All Xen servers run ubuntuHardware platforms include Sun x2100, x4x00System setup to clone zones

VMWare used primarily on streaming services (Windows based)

Using virtualization as a tool for change/revision management

<shameless plug>- more information on change/revision management at Ramon’s “Pure Production” talk

later this week</shameless plug>


Future Consideration

Private Network to manage global zones– “Real root” not accessible– Single VLAN for network booting

Virtuozzo

Solaris zone cloning

Hardware-level virtualization– Sun LDOMs will create a hardware hypervisor

VMWare ESX

PXE Boot - VMWare imaged systems

Technology

Methodologies, strategies and experiences Virtualization