February 10, 2015

Integrating Parallels Virtuozzo container in Citrix Xen server

Linux General,

We are trying to install virtuozzo 4.7 in a virtual Machine that has got centos running on it. Virtuozzo installation in this VM goes fine and the VM prompts for reboot post installation. During boot operation, the VM console freezes with lot of errors whereas you can still login to the Virtual machine using putty…

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February 10, 2015

Change VLAN ID using VMware Infra Client or Vsphere client

VMware,

This guide will help you to change the VLAN ID using the VMware Infra Client or Vsphere client. Below are the information that relates to adding and removing VLAN IDs to and from a portgroup, when the following symptoms are observed.

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February 10, 2015

Fixing a corrupt VHD file

Virtualization,

There could be many possible causes why your VHD may become corrupted. More often administrators tend to restore the backup from the snapshot catalog. This is to ensure an uptime guarantee. However, if we have enough time or in the event of not having a snapshot backup our options are very limited. Below are a…

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November 7, 2014

Virtual Machine Cannot Start (Vmware) – ESX/ESXi – 5.0

VMware,

There will be situations where the VM on a host fails to start without showing any progress when the power state is reset. This can be caused by a hung process on the host. Solution: SSH into the host on which the VM is running and run the following commands:

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November 5, 2014

Increase VMware VM performance by placing the Swap file in an alternate location – ESX/ESXi 5.0

VMware,

n this post you will see how to Increase VMware VM performance by placing the Swap file. By default, a swap file is created when a virtual machine is powered ON under a ESXi host. Swap files normally are stored in the same location as in the VM’s configuration file, it could be a VMFS…

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October 3, 2014

Preventing WordPress XML-RPC DDOS Attack

Content management system,

WordPress XML-RPC pingback exploits are used in a number of DDoS attacks in the recent times. WordPress is widely used by many websites that uses a content management system, any vulnerability in the WordPress could compromise the website and break down the Network integrity. Hence it is important to secure and mitigate wordpress websites from…

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July 4, 2014

How to Change the Pool Master in Citrix Xenserver

Cloud Infrastructure,

In Xenserver pooled environment, if the pool master node goes unresponsive due to some reason. We will not be able to access the slave nodes and its corresponding VM's from Xencenter. At this time, if we are able to manually SSH into the pool master. We can execute the following commands to make a slave…

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June 10, 2014

Steps to Fix VDI Not Available Error in Citrix Xenserver

Cloud Infrastructure,

During a Reboot of a VM at some unavoidable circumstances, the Startup logs might end up with "VDI not available" error. Follow the below steps to fix this: Determine the UUID of the Storage Repository and the VDI that’s exhibiting the issue

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May 30, 2014

How to Fix – When Xenserver Host Stuck in Maintenance Mode

Cloud Infrastructure,

In this post you will see how to fix Xenserver Host Stuck in Maintenance Mode. Whenever we restart the xapi service (using either service xapi restart, or xe-toolstack-restart) the API will work for about 30 seconds and then it will stop working and any command we run from that server will show something like this:

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May 19, 2014

Steps to be taken when a VM goes in Read-only mode

VMware,

Whenever there is a file system inconsistency involved, the system mounts in Read-only mode to prevent damage to the system. In Xen, if you come across such a situation you can try using the following methods to mount that back in write mode. Boot the VM in single user mode. One can get into single…

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