XenServer reviewed by an avid Citrix and VDI engineer
Updated February 12, 2016
XenServer reviewed by an avid Citrix and VDI engineer
Score 7 out of 10
Vetted Review
Software Version
6.2
Modules Used
- Standard Virtualization for VDI workloads some Server
Overall Satisfaction with XenServer
The XenServer workloads I have set up and currently provide are primarily for clients. These workloads cover anything from an IT lab, VDI and Server workloads for the entire data center. It is a mixed use hypervisor in most environments where it is placed for a purpose (such as VDI) at a cost savings and management supplement due to its ease of use.
- Manages upgrades to the pool of hypervisor hosts with relative ease through a console (if licensed).
- Makes it easy to create machine templates and clones and move them around within the pool of hosts.
- Handles failures reasonably well through the use of the pool database copied on each host
- Adding or presenting additional storage to the host can often be a task that is far more involved than competitive products.
- The product can require reboots more frequently than competitors due to the DOM kernel getting "hung up".
- Sometimes when a virtual machine is deleted it still leaves behind orphaned vdisks.
- Recovering from the loss of a host can sometimes cause virtual machines to require lengthy command prompt scripting to fix so they can be powered back on from another host.
- Positively, the ability to implement a XenServer pool for VDI workloads is a fast process. Thus a faster project getting into the pilot phase.
- Negatively, XenServer has caused outages at client sites due to the pool master failing and a subsequent member not taking over properly (VDI).
- Negatively, XenServer has failed to allow easy addition of storage or expansion to a SAN drive which required an outage to occur in order to properly see the new free space for growth.
XenServer like the similar product I've used in the hypervisor market stacks up well in regards to compatibility with virtual machine [operating systems]. It is also capable of allowing for large, powerful VMs to be run upon it. The main selection of XenServer in environments I've worked within was due to the price and supportability it entailed. With a Citrix license of XenDesktop you get the XenServer license included which means direct price savings over competitors (added costs) and a support channel for issues.
XenServer Feature Ratings
Using XenServer
Desktop workloads, access to applications through server virtualization, Active Directory through server virtualizations, web hosting, file services, print services, email services, database support and programming engines, classroom management services and student management service. The platform powers services for backup, recovery, banking services, patient management and doctor records management. Anyone from students, teachers, professors, nurses, doctors, administrators, CEOs and owners use the platform in some way.
3 - As a consultancy based role there is a small pool of engineers certified and experienced with the platform. The skills required to support XenServer include knowledge of NAS and SAN based storage; this required knowledge on the network and types of switches and interfaces leveraged by each technology as well as the ability to use a command line and scripts for a Linux based operating system.
- Virtual Desktop infrastructure
- Server workloads for branch offices
- Server workloads for an entire company
- Disaster Recovery capabilities for failed hardware
- Allow access to GPUs for graphical workloads within a virtual desktop implementation
- Cross site DR through use of SAN replication and some third part tools for backup management
- Creating a lab environment within a production footprint without requiring excessive processing or power for what typically requires dedicated equipment
- Replacing entire data centers
- Replacing all compute within a branch office
- Fast deployment of compute resources for acquisitions or new locations opening
Evaluating XenServer and Competitors
- Price
- Product Usability
- Prior Experience with the Product
- Vendor Reputation
- Existing Relationship with the Vendor
- Third-party Reviews
Price has always been a huge factor in the decision which ends up with XenServer in an environment. The XenServer product is licensed within all Citrix Enterprise level XenApp and XenDesktop suites. The latest edition of these products now includes full support and the usage of the XenCenter console which greatly enhances the ability to manage the solution.
Looking into the future many organizations are interested in how to begin or further leverage an investment in the cloud. The could mean Amazon, Microsoft, VMware, IBM or another solution provider to be able to offload the management and initial purchase required to provide the compute needed for their environment. The ability to move a datacenter effortlessly and expand or contract with little to no loss of investment is a huge proposition with evaluating this type of workload platform.
XenServer Implementation
- Professional services company
My company is a professional services consultancy so I can't say I've worked with anyone but myself upon becoming certified with the solution and working with colleagues already experienced with the product. The name of the company is iAccess, Inc. in Richmond, VA.
Yes - Procurement of all necessary hardware is the first phase (blades, network cards, chassis, rack, power cords, network cables, switches, routers, hard drives, memory). The next phase is the checking to ensure all components are in place and functioning as expected (memory burn, etc). Storage is presented to the expected network interfaces or fabrics for the solution and the local hard drives are loaded with the installation of the XenServer kernel and operating system. Each server is installed manually (can be through PXE depending on size) and added to an initial pool to automate connectivity to storage and naming of networks.
Change management was a big part of the implementation and was well-handled - Ensuring that all groups are involved and prerequisites defined early help support a good implementation with change management or controls. Being as the solution requires network, storage, backup, power, data center, rack, cabling there are typically a few teams within an organization that must be present and knowledgeable to their tasks.
- Incompatible hardware, check the HCL but also check with the vendor
- Storage not being visible due to lack of zoning, or correct zoning
- Networks not trunked to the appropriate switch ports for the virtual networks creates an unnecessary delay
XenServer Training
- Self-taught
It is relatively easy to learn, the install with current releases makes things even easier at the time of installation and initial configuration. There are some Linux commands that you'll have to learn for some tasks, but the documentation and searching the Internet will allow you to get down the right path with relative ease.
Configuring XenServer
Ensure you review the HCL (hardware compatibility list) prior to planning to install XenServer on a host system (hcl.xensource.com). Ensure you are leveraging hard disks for installing XenServer (doesn't support SD cards - at least last time I've checked, which could be outdated info). Use like hardware (until the next release 6.5 SP2?).
No - we have not done any customization to the interface - I wouldn't consider adjusting the layout of the interface as customization. You can adjust what is shown from the environment rather easily with built-in console tools.
Some - we have added small pieces of custom code - Some custom code or tweaks that have been done in the past were put in place to ensure the Dom0 Kernel disks didn't fill up with logging data which was initially and issue in large VDI based environments. So essentially a script that would run to remove old log files.
I haven't seen any need to customize XenServer for the environments I've worked within. It is worth mentioning that XenServer is generalized by its implementation by CITRIX; however, Amazon uses the source code from XenSource to build and manage AWS which shows the ability to have a fully customized setup which is also quite robust.
XenServer Support
Pros | Cons |
---|---|
Quick Resolution Good followup Knowledgeable team Problems get solved Kept well informed No escalation required Support understands my problem Support cares about my success Quick Initial Response | None |
On one incident occasion there was a complete lack of compatibility with a converged network adapter for a vendor which was stated to be fine with workloads on XenServer. This became an issue and incorrect information when a VDI environment was built but there was a lack of ability to stream the virtual disk image leveraging Citrix Provisioning Services. Citrix provided incredible support involving the hardware vendor and lining up options to replace the incompatible card to ensure project success and positive momentum. At this same time update drivers for XenServer were shared and made a world of difference in driving success with the project.
Using XenServer
Pros | Cons |
---|---|
Like to use Relatively simple Easy to use Technical support not required Well integrated Consistent Quick to learn Convenient Feel confident using Familiar | None |
- Managing virtual machines and adjusting the view within the XenCenter console is very easy
- Creating a new virtual machine is easy
- Adding and browsing storage repositories is easy
- Changing or updating storage repositories is very difficult.
- Bringing up a failed hosts virtual machines can occasionally require some cumbersome scripting or command line work.
- It is difficult to manage the virtual switches.
XenServer Reliability
Integrating XenServer
- System Center Operations Manager
Very low level of difficulty, lots of integration is built into the items above and there are management packs for easy SCOM integration.
- Monitoring Solutions
- Networking Solutions
Yes, there are quite a few that have options to pull metrics from the XenServer hosts in regards to the services supported on the hosts and their workloads
- File import/export
- Single Signon
- API (e.g. SOAP or REST)
Dont forget to look beyond the big names in solutions for integration capabilities, there are numerous smaller companies doing great feature integration. Use that search engine!
Relationship with Citrix
Working as a partner there wasn't any need to negotiate. Options for adding software assurance or support are available, typically with a limited period included.
No special advice here, learn about the product, have licensing laid out simply and bullet point the features of interest. Ensure you choose only what you need, or what you want. No need to upgrade or go up a level if it doesn't fit.
Upgrading XenServer
Yes - On occasion the upgrade can hang or create an issue for needing a rebuild. This is typically within a pool of resources so it's a quick fix. Current releases have improved the upgrade experience and resolved a number of snags that used to occur so the upgrade is quite simple now and low in impacts.
- 64-bit Kernel, drastically improves scalability and performance
- Improved support for vGPU options
- Ability to create VM's with much larger virtual hard disks
- More supported GPU options
- Storage connectivity options improved or augmented (SMB option!)
- Further integration with virtual desktop environments (XenDesktop)
Yes - Simply by adding the licensing to the license server and pointing the resource pool to the licenses. Very nice experience.
No - Likely no need in most environments as XenServer is included for VDI workloads