Skip to main content

Windows Azure fault domain and upgrade domain

Fault Domain: In simple words, fault domain can be considered as a single point of failure. For eg:, servers hosted in a rack in a data center can be considered as a fault domain, because power failure to the rack will bring down all the servers in it. During deployment time, the instances in a role are assigned to different fault domains, to provide fault tolerance (only when there are multiple fault domains)

Upgrade Domain: This concept is applicable during a deployment upgrade.Each upgrade domain can be considered as a logical unit of deployment. During an application upgrade, it is carried out on a per upgrade domain basis, ie the instances in the first upgrade domain are stopped, upgraded  , brought back to service, followed by the the second upgrade domain. Thsi ensures that the application is accessible during the upgrade process though with reduced capacity
Labels:

Comments

Post a Comment

Popular posts from this blog

Install nested KVM in VMware ESXi 5.1

In this blog, I will explain the steps required to run a nested KVM hypervisor on  Vmware ESXi. The installation of KVM is done on Ubuntu 13.10(64 bit). Note: It is assumed that you have already installed your Ubuntu 13.10 VM in ESXi, and hence we will not look into the Ubuntu installation part. 1) Upgrade VM Hardware version to 9. In my ESXi server, the default VM hardware version was 8. So I had to shutdown my VM and upgrade the Hardware version to 9 to get the KVM hypervisor working. You can right click the VM and select the Upgrade hardware option to do this. 2)In the ESXi host In /etc/vmware edit the 'config' file and add the following setting vhv.enable = "TRUE" 3)Edit the VM settings and go to VM settings > Options  > CPU/MMU Virtualization . Select the Intel EPT option 4) Go to Options->CPUID mask> Advanced-> Level 1, add the following CPU mask level ECX  ---- ---- ---- ---- ---- ---- --H- ---- 5) Open the vmx...
5 comments
Read more

Virtual fibre channel in Hyper V

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...
2 comments
Read more

Windows server 2012: where is my start button??

If you have been using Windows Server OS for a while, the one thing that will strike you most when you login to a Windows server 2012 is that there is no start button!!.. What??..How am I going to manage it?? Microsoft feels that you really dont need a start button, since you can do almost everything from your server  manager or even remotely from your desktop. After all the initial configurations are done, you could also do away with the GUI and go back to server core option.(In server 2012, there is an option to add and remove GUI). So does that mean, you need to learn to live without a start button. Actually no, the start button is very much there .Lets start looking for it. Option 1: There is "charms" bar on the side of your deskop, where you will find a "start" option. You can use the "Windows +C" shortcut to pop out the charms bar Option 2: There is a hidden "start area"in  the bottom left corner of your desktop...
3 comments
Read more