The Technology Chronicle

Ubuntu P2V conversion is not as straight forward as other Linux machines with a root user. This is because we use a non-root user by default for managing Ubuntu machines and the root credentials are not known to us. So how do you convert a physical Ubuntu VM to virtual without the root credentials? Here are the steps PS: please note the steps are for VMware vCenter standalone converter 5.5 1.Edit VMware configuration files converter-agent.xml and converter-worker.xml files present in C:\ProgramData\VMware\VMware vCenter Converter Standalone , update the useSudo flag from false to true 2. Reboot the VMware converter standalone agent service

Issue 1: While trying to add a new host to a Pool in XenCenter, I was getting error "internal connection failed no route to host " Solution: It was quite simple actually, but since I couldnt find it mentioned in any knowledge bases or articles, I am noting it down here. The machine where XenCenter was installed couldnt resolve the Xen host name. The machines were not added to domains and hence no DNS entries were there. So I had to add a host entry to the XenCenter machine to help with the name resolution Issue 2: Enabling AD authentication via XenCenter fails with error "clock skew detected with active directory server" Reason: This happens because of the time difference between XenServer and AD server Solution: Update NTP server list of the XenServer and point it to the AD server of the domain. Steps below From the XenServer console, go to 'Network and management interface"->Network time(NTP) Select option "Remove all NTP se...

This week, I was trying to get my head around a new Hypervisor(new for me, obiviously), ie XenServer. Though it is pretty much same as ESXi and is free as well, there are some striking differences as well.The observations are based on the free version of Citrix XenServer version 6.2.0 - While ESXi needs a paid vCenter to manage multiple hosts, you can use the free XenCenter software to manage multiple Xen hosts - Latest version of Xen server doesnt have the equalent of DRS or DPM. There was a feature named workload balancing, which was strangely discontinued in version 6.2.0 stating reason that there are no takers for it. - It does offer a High Availability of VMs using pool based clustering of hosts -XenMotion is the equalent of VM live migration, but it is restricted to one VM at a time -XenCenter doesnt have a web client like vCenter -There was a tool named XenConvert used for physical to virtual conversion, but it is retired as well. -There is an option named Dynamic...

Virtual fibre channel option in Hyper V allows the connection to pass through from physical  fibre channel HBA to virtual fibre channel HBA, and still have the flexibilities like live migration. Pre-requisites: VM should be running Windows Server 2008, 2008 R2 or Windows Server 2012 Supported physical HBA with N_Port Virtualization(NPIV) enabled in the HBA. This can be enabled using any management utility provided by the SAN manufacturer. If you need to enable live migration, each host should be having two physical HBAs and each HBA should have two World Wide Names(WWN). WWN is used to established connectivity to FC storage.When you perform migration, the second node can use the second WWN to connect to the storage and then the first node can release its connection. Thereby the storage connectivity is maintained during live migration Configuring virtual fibre channel is a two step process Step 1: Create a Virtual SAN in the Hyper-V host First you need to click on Vir...

Now that we have had  a look at how to do the Installation and initial configuration of Hyper V Server 2012 in my previous blog post , lets start on the management part. In this blog, I will explain how to manage your Hyper V installation from a Windows 8 machine Remote management: Since Hyper V Server 2012 server core machine, you may want to manage it remotely using the familiar GUIs and MMC consoles. You can do so remotely, but before that you need to set the firewall rules to allow that.In the command prompt windows of the server, get a poweshell prompt by typing in "powershell". Now you can execute the following powershell command Enable-NetFirewallRule -DisplayGroup * Note: I used this command since it is my test network, you may want to lockdown the firewall rules a bit if in case of production network Inorder to connect to the Hyper V server using MMC from my PC, I had to run the following command in the PC command prompt cmdkey /add:<ServerNam...

Having heard a lot about the latest free virtualization from Microsoft, Hyper-V server 2012 , I coudnt resist giving it a whirl.. After all, it is not daily that Microsoft comes out with "free" offerings ;) Let us admit it..Ever since the advent of virtualization, we have few physical servers lying around.All of them have joined the virtualization bandwagon. My case was no different, so I decided to try out  Hyper-V server 2012 as a virtual machine in VMware Workstation 8 installed in my PC. Installation preparation: Few things to be taken care before you start the actual installation 1)Download the Hyper V Server 2012 ISO from Microsoft site: http://technet.microsoft.com/en-US/evalcenter/dn205299.aspx 2)VMware workstation 8 does not have Server 2012 in the Windows OS list.Hence you need to select the option "Windows Server 2008 R2 x64" when you create the Virtual machine 3) There is a small tweak to the Processor settings that should be d...

vMotion is the process of moving running virtual machines from one ESXi host to another.The disk files are not migrated(they stay in the shared storage), only the VMs memory and CPU processing moves from one server to another. In fact if you ping the VM while it is moving, you may at the most loose at most one or two ping packets. vMotion happens in three stages: -vCenter server verifies that teh VM is in a stable state -VM state is copied over to the destinatiom. State includes the memory, registers and network connections -VM is resumed in the destination host vMotion can happen due to any of the following reasons: - Balance the load on ESXi hosts using DRS -When the VMs are being moved off from a host so that the host can be shutdown by DPM(distributed power management) -You need to intsall patches using update manager or do a hardware maintenance, the VMs are migrated using vMotion and host is put into maintenance mose vMotion requirements: -You will need vSphere E...

The Linked clones concept is similar to the normal VM cloning process, but with a storage saving twist ;) When we create a linked clone, a new VM is created from a base VM , at the same state. This clone with use the base VM's hard disk for all read operations, however all writes to the disk ie any change to the data from the original disk is written on  a new disk. This is very similar to the concept of snapshots where the original VMDK is read only and all subsequent writes are done to a delta disk. The main advantage of using Linked clone is to avoid deduplication of data. You can have n number of VMs created from the base virtual machine, but the base disk remains the same. This will considerably reduce the disk space usage, especially in cases like web server farms with multiple servers

After server and desktop virtualization, VMware is now focusing on network virtualization. Essentially the company has been focusing so far on the 'compute' market for Virtualization and now it has started working on a similar product for Network. Lets admit it, Networks take more time to provision. With virtualization coming in, the creation of Servers, desktops etc now takes minutes when compared to hours/days/weeks situation in the pre-virtualization era. But if we have a new network requirement for the VMs, it can be sorted to an extend using vSwitch. What if the requirement goes beyond that? Say a router /firewall/VPN that should be used by the VM. Of course, we should get in touch with the networking guys and it could take some time for the stuff to get sorted out With NSX, Vmware aims to address this bottle neck. The idea is to provision,backup and manage networks similar to how you manage your VMs now. There will be logical switches,routers, firewalls and VPNs.You ...

If the VDP backup fails , the following troubleshooting steps can be used SSH to the the VDP appliance and browse to the /usr/local/avamarclient Search for logs related to the VM :   grep -r -a "VM_NAME" ./* If you suspect it is snapshot related issue : grep -r -a " VM_name" ./* | grep "FATAL" To be more specific and to check messages for a certain date, try searching using the date : grep -r -a " VM_name" ./* | grep "2013-08-02" Sometimes we could get very useful information from the "info" messages as well. Inorder to narrow down to the same, you can use the command: grep -r -a "VM_name" ./var-* | grep "2013-07-03" The baove command will search only through the 'var-proxy' directories. It will display the entire log file. You can less it to view details for a specific date eg:  less ./var-proxy-5/VMGROUP1-1378306800496-35fj52c29f48eeejef090b27edaeba3d868719e8-4016-vmimagew.log /2013...

VMware has released the latest version of vSphere in VMworld 2013 .Release 5.5 includes a number of significant improvements as well as new features over the past releases. Lets have a look. What is new? Application HA: The HA feature extended to applications like MSSQL,Tomcat,IIS,TC server runtime etc.It can monitor applications and take actions liek restarting the application, resetting the VM , raise an alarm or send email notifications .A vFabric Hyperic should be installed in each guest OS.Also an AppHA virtual applicance and Hyperic server is required for thsi to work Reliable memory Technology: This enables ESXi to analyze the reliability of memory ,predict failures and stop using unreliable parts of memory. It will also help put critical processes like watchdog and hostd in the reliable area.  Flash Read Cache: This was previously avaliable in Beta as vFlash. This technology leverages the local flash devices reources in a host to provide a clustered flash resources...