Earlier today Citrix announced the first public beta of a XenServer 5.6 Feature Pack 1 (codename Cowley). This is a significant release as it finally includes the Open vSwitch technology and the distributed virtual switching capabilities that come with it.
The early bits of Open vSwitch appeared online in August 2009, along with a technology roadmap that clears the intention to compete against the VMware vNetwork Distributed Switch architecture and the Cisco Nexus 1000V software switch. It took almost an entire year to reach version 1.0. Meanwhile Open vSwitch became a key component of the Xen Cloud Platform (XCP) networking infrastructure, another project supported by Citrix.
OpenFlow based virtual switches in each server can be logically pooled into a single fabric by an external distributed virtual switch controller to build a dynamic, multi-tenant, programmable datacenter fabric that supports key innovations in cloud computing, as well as allowing us to take advantage of standard x86 CPUs to run a set of rich edge packet-processing functions to secure, direct, filter and otherwise control the delivery of cloud based applications.
With the Open vSwitch in place, the Open Stack open source cloud orchestration layer will be able to exert direct control over the data center fabric to deliver a rich, enterprise ready network layer with powerful controls for security, multi-tenancy, load balancing, monitoring, compliance, charge-back and more.
He also described the potential of the OpenFlow protocol (through 3rd party contribution):
The Host sFlow agent exports hypervisor performance statistics (both the physical server statistics, CPU, memory, I/O) as well as per-VM performance statistics (similar to libxenstat). Since switches, routers and load balancers (Open vSwitch, Vytatta, NetScaler) now exist as software entities, you cannot manage network performance without understanding the performance of the host since an apparent network performance problem could now be due to a lack of computational resources on the server. The sFlow standard provides the comprehensive, scalable monitoring solution needed to manage performance in converged environments.
In addition to providing physical and virtual server statistics, the Host sFlow agent can automatically configure sFlow in the Open vSwitch, greatly simplifying the task of coordinating performance monitoring across the data center.
The Host sFlow agent has been built and tested on XenServer 5.6. The agent is tiny (around 50K) and imposes a negligible load on the hypervisor (it spends most of its time asleep, waking up occasionally to grabs some counters, sends a UDP datagram and go back to sleep).
Recently, Crosby also revealed that following versions of Open vSwitch will support Intel Single Root I/O Virtualization (SR-IOV) technology.
The next version of XenServer anyway has more than just distributed virtual switching. The list of new features include:
- VM Protection & Recovery
The capability to configure scheduled snapshots and (optionally) export entire virtual machines.
- Web-based Self-Service Provisioning Portal
Provides browser-based access to selected virtual machines by delegated administrators.
- Boot from SAN with multi-pathing support
Boot XenServer hosts with Fibre channel HBAs from a SAN, with multi-pathing support.
- HA Restart Priority
Configure HA policies to restart specific VM(s) first, such as StorageLink Gateway VMs or the Distributed vSwitch Controller VM.
- Support for multi-vCPU in Dom0.
- Automatic reclamation of storage space after VM snapshots have been deleted.
- Support for Microsoft Windows 7 SP1, Windows Server 2008 R2 SP1, Red Hat Enterprise Linux (RHEL) 6.0, CentOS 6.0, Oracle Enterprise Linux (OEL) 6.0, Debian Squeeze (32 and 64-bit), and Novell SUSE Linux Enterprise Server (SLES) 11 SP1 guest OSes
- Support for RHEL 5.x as “generic” guest OS
- OEM of Brocade HBA drivers and command-line tools
- Local host caching of VM images to reduce storage TCO for XenDesktop VDI deployments (this feature will require a future version of XenDesktop to work)
The web-based self-service provisioning portal probably comes from the integration with the VMLogix technology that Citrix acquired exactly one month ago.