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Monday, 7 January 2013

What's new in Citrix Xenserver 6.1


What's new in Citrix Xenserver 6.1
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Citrix has recently released XenServer 6.1, I wanted to let you know about some of new features and functions to look out for in this release.

Version 6.1 features Cloud integration capabilities and a storage feature called Storage XenMotion that will bring agility as it allows IT executives to freely move virtual machines without the need for shared storage. XenServer 6.1 is integrated with Apache CloudStack and Citrix CloudPlatform to simplify cloud adoption for its users.

Among other features, XenServer 6.1 includes improved networking and security capabilities, increased supplier compatibility and automated virtual machine conversion tools as well.

Here's a quick look into each feature:

Storage XenMotion

Storage XenMotion allows virtual machines that are currently running to be moved from one host to another.  Including VMs that are not on the same storage or even shared storage between hosts, and between hosts that are not in the resource pool.

  1. Re-balance or move VMs between pools i.e. moving a VM from dev environment to production.
  2. Perform software maintenance i.e. upgrading/updating standalone hosts without VM downtime.
  3. Perform hardware maintenance i.e. upgrading standalone XenServer host hardware without downtime for the VMs on that host.
  4. Reduce deployment costs by using directly attached storage on the host.
  Live VDI Migration

Live VDI migration allows admins to relocate a VM’s virtual disk image without shutting down the VM.

  1. Move a VM from local storage to shared storage
  2. Move a VM from a dev environment to production.
  3. Move between tiers of storage when the VM is limited by your storage capacity
  4. Perform upgrades on your storage arrays

Networking Enhancements

Some of the networking enhancements include support for Link Aggregation Control Protocol (LACP) – industry standard network bonding features to provide fault tolerant and load balancing of network traffic.   

Source Load Balancing (SLB) improvements like up to 4 NICs can be used in an active/active bond.  Whereby improving your total networking throughput and fault tolerance in cases of hardware failures.  The algorithm has also been changed to reduce load on switches in large deployments.   

Multi-Tenancy improvement to allow admins to restrict a VM to send and receive traffic on specific MAC address and a number of IPv4 or IPv6 addresses, without needing to rely on vLANs and switch management.  When these extensions are deployed, VMs cannot impersonate any other VM, or intercept traffic intended for another VM.  The extensions will increase security in those environments where VMs cannot be fully trusted.

vLAN scalability removes a previous limitation which caused VM deployment delays when large amounts of vLANs were is use.  This does allow the admins to deploy large numbers of vLANs quickly to your XenServer pools.   

Emergency Network Reset provides a simple mechanism to reset/recover a XenServer host’s networking state, allowing your admins to revert to a known good state.

IPv6 Guest support
will enable the use of IPv6 within guest operating systems, allowing the admins to plan appropriately for network growth.

Citrix XenServer Conversion Manager

Enhancements for the Guests is the inclusion of the Citrix XenServer Conversion Manager, this will enable batch import of VMs created with VMware products into a XenServer pool to reduce the costs of converting to a XenServer environment.  

Also included is a new mechanism for the installation of XenServer tools, as the tools are delivered as industry standard Windows Installer MSI files now.  This will enable the use of 3rd party tools to deliver and maintain the installation/upgrade of the XenServer device drivers. 
 

Guest OS Support

More guest OS support for Ubuntu 12.04, CentOS 5.7 and 6.x platforms, Red Hat and Oracle Enterprise Linux 5.7 and 6.x,  and experimental support for Windows 8 and Windows Server 2012.


Further Reading:

Installing XenServer 6.1 as a VM in VMware Workstation (COMING SOON !!)