Second edition of VMware Site Recovery Manager is out

The second edition of VMware SRM, officially named as VMware vCenter Site Recovery Manger 4, was released recently. The product is responsible for automated disaster recovery of complex virtual environments. The recent version is fully compatible with VMware vSphere platform and provides these new important features:

• many-to-one failover - this means that one site is able to recover from multiple sites failures
• expanded support of storage vendors - those who provides storage replication solutions over FC, iSCSI or NFS, 12 generally. Among them belongs DELL, IBM, HP, EMC, LSI and others.

For more information on VMware SRM 4 visit the release notes and product home page.

VMware or Citrix?

Citrix released their virtualization solution named XenServer (from version 5, article XenServer is free) for free but only the time will show if it was a right decision. At first glance, it seems like a marvelous thing but there are some facts which should be investigated first. Together with XenServer, it was released central management solution XenCenter.

Let's have a look at their rival VMware (vSphere 4). XenServer is fully comparable to VMware ESX or ESXi. But what about XenCenter management? It's something more than VMware vSphere client but not so valuable as VMware vCenter Management Server. Citrix XenCenter is not the right choice in case of comparison to vCenter. The right one is Citrix Essentials but this one is not for free already. The main differences between Citrix XenCenter and Essentials are:

• XenCenter is missing alerting capabilities like send me an email when "CPU usage is too high" or when some error condition like "virtual machine power on failure" appears
• XenCenter is missing high availability support
• XenCenter is not able to show you performance data older than one day for physical or virtual servers
  

Now, let's try to propose a simple high availability (HA) solution based on Citrix/VMware products and compare their prices. Let's suppose we have 2 (3) entry level servers where each have 2 CPUs with max 6 cores per CPU (6 CPUs total). The servers are connected to a shared disk storage. The CPU speed or memory capacity is not important now. And we require HA solution to protect our virtual machines from hardware failure. Follows the analysis:

- Citrix Essentials Enterprise (1 license = 1 server):

• XenServer - 2 licenses = 0$ (3 lic = 0$)
• Essentials Enterprise - 2 lic = 5500$ (3 lic = 8250$)
• Essentials Preffered Support (optional) - 1 lic = 1500$
  
• Total cost = 7000$ or 9750$ for 3 servers
  
• Total cost without support = 5500$ or 8250$ for 3 servers

- VMware vSphere 4 Standard Edition (1 lic = 1 CPU):

• vSphere 4 Standard - 4 licenses = 3180$ (6 lic = 4770$)
• vShpere 4 Standard 1y Gold Support - 4 lic = 1092$ (6 lic = 1638$)
• vCenter 4 Foundation - 1 lic = 1495$
• vCenter 4 1y Gold Support - 1 lic = 545$
• Total cost = 6312$ or 8448$ for 3 servers
• Support is mandatory

- VMware vSphere 4 Essentials Plus Bundle (1 lic = 1 CPU)

• Licenses for 3 hosts plus vCenter Server for Essentials plus 1y Gold Support = 3624$
• Total cost = 3624$ for 2 or 3 servers
  

The prices of proposed solutions are quite different. In my opinion, the most valued solution is based on new VMware product line vSphere 4 Essentials.

There are rumors that VMware is the most expensive solution. I don't think so if I check the numbers above. Citrix's solution not covered by support is cheaper then VMware's solution with support but only for 2 servers. If I would like to add third server I would have to pay another license in case of Citrix. In case of VMware, I have still one spare license so I will use it. At first glance, XenServer seems to be free of charge but the price of added value by Citrix Essentials doesn't scale as well as in case of VMware vSphere 4 Standard Edition or vSphere 4 Essentials Plus. And what is your opinion to the topic?

VMware vSphere - OVF support

OVF or Open Virtualization Format is an open DMTF standard with intention to package and distribute virtual machines or virtual appliances among various hypervisors independently on hypervisor and CPU architecture.

VMware supports OVF format and actively participate on its development . It is supported on ESX 3.5 and VirtualCenter 2.5 but the implementation doesn't support full OVF feature set. (draft standard, version 0.9). VMware vSphere 4.0 has full native support of OVF format in version 1.0. Beside, there exists standalone VMware OVF Tool 1.0 which brings OVF support for products like VMware Workstation or VMware Server.

OVF is a packaging format for software appliances. For example, it may contain tested LAMP stack prepared for simple deployment in production. It is a way how to transport virtual machine templates portably. OVF package may contain single or more virtual machines which must be installed (deployed) before they can be run. It is not run-time virtual machine format like VMDK. Further, it provides content verification and integrity checking.

Compared to VMDK format, OVF defines complete virtual machine - virtual hardware configuration including CPU, memory, storage, networking and virtual disks. On the other hand, VMDK is in charge of virtual disks only.

Are there available any OVF packages? Yes, for example there exists OVF of VMware vCenter 2.5 for Linux or vCenter Admin Portal and many others at VMware Virtual Appliance Marketplace.

VMware vCenter Converter 4.0 was released

The previous version of Converter was at 3.0.3 for a long time. The new standalone version is much similar to the one included in Virtual Infrastructure 3.5 (VI 3.5).

Before it, there were available two editions - Starter and Enterprise where the second one is part of VI 3.5. Here are the additional features of Enterprise edition compared to Starter:

• it supports multiple migration jobs
• it supports cold migration
  
• it is part of VI3.5 only (particularly VirtualCenter server)

What new brings us latest revision? It is free of charge, it has larger set of supported operating systems as source or it allows you to select the target virtual disks. Newly, it can migrate sources with RedHat, SUSE or UBUNTU Linux. Furthermore, it is able to power off the source after migration finishes. The more comprehensive comparison of the version 4.0 and the version included in VI3.5 is presented by this picture.

VirtualCenter for Linux

It seems VirtualCenter Server for GNU/Linux is being prepared and might be released with the next version of Virtual Infrastructure or its successor called VMware vSphere 4.0. It's going to be presented at the incoming virtualisation event VMworld Europe 2009. The official abstract of technical session covering this topic is published at VMworld Europe 2009 website.

VMware VirtualCenter running inside virtual machine - part one

I finished another installation of virtualized environment recently. I had to get rid of old machines and to deploy virtualization on couple of new SUN Blade 6250 modules (installed in SUN Blade 6000 Modular System) connected to SUN StorageTek 2510 iSCSI disk array. The final solution had to pass high-availability conditions.

The VMware ESX Server 3.5 hypervisor was installed on both of blades and deployed in high-availability mode. It requires VirtualCenter Server to be installed to configure VMware cluster. But does it have to be installed on a standalone machine?

VMware officially supports VirtualCenter Server running inside a virtual machine (further denoted as VC VM). Such configuration supports VMware HA as well. But it will pay to keep some basic rules in mind. Let's go over them:

1. VC VM should have allocated enough resources - set CPU/MEM reservations and shares sufficiently to avoid of running out of resources because this machine is vital for virtual infrastructure. It has to be prioritized over the other virtual machines.
2. Remember to monitor the machine. That means configure a simple alarm to check CPU/MEM usage. E.g. it can be trigerred if the resource usage is over 90%.
   
3. VC VM should be deployed with security rules in mind. Define which users can access it and limit their permissions (configure user roles with help of Active Directory).
   

The list above doesn't contain obvious rules like hardware requirements for server, installation of MSSQL database separately and similar. These rules are the same as for standalone VirtualCenter installation. Next, we are going to discuss the question what to NOT perform with VC VM:

1. Never cold-migrate VC VM! The machine has to be powered off first.
2. Don't try to clone VC VM if you are deploying version of Virtual Infrastructure before 3.5. The version 3.5 supports virtual machine cloning on the fly.
3. Try to avoid of any operation with VC VM AKA virtual machine hardware reconfiguration which may require to power it down. If you need to do it, connect directly to the related ESX host, power VC VM off and reconfigure it without loosing management connection.
   

It remains to discuss the stuff around VirtualCenter virtual machine installation and to realize if such configuration will bring something new compared to standalone installation. But about it by the next time.