Azure Linux Support Team

Support for Linux on Azure

How to: Resize Linux osDisk partition on Azure

Most Linux images on Azure will by default have 30GB size for the osDisk and that is something that you might want to resize moving forward. Resizing the partition is really simple on Azure and we can be done by the following procedure: a) Stopping and deallocating the VM on the portal or Azure CLI… Read more

Linux Recovery: Fixing non-boot issues related to Kernel problems using chroot

In a previous article, it was described how to manually fix kernel related issues that could cause a Linux VM to not boot properly. There is also an option where you can use steps to use CHROOT and then use tools to automatically fix these same issues without the need to manually edit files. Assuming… Read more

Linux Recovery: SSH daemon is not starting up properly

You have noticed that you lost SSH connectivity to a Linux VM and after examining the boot diagnostics you see messages related to errors in the SSHD configuration. The error around invalid configuration might be simply: Starting sshd: [FAILED] There were a few instances seen in SUSE and Red Hat where errors are seen due… Read more

Linux Recovery: Cannot SSH to Linux VM due to file system errors (fsck, inodes)

When a Linux VM requires fsck to repair possible file system issues, manual intervention will be required. Below you can see four examples on how to identify file system issues by looking at the boot diagnostics on a given VM under: Virtual Machines > VMNAME >  All settings > Boot diagnostics Example (1) Checking all file systems. [/sbin/fsck.ext4… Read more

Linux Recovery: Using CHROOT steps to recover VMs that are not accessible

You are facing an issue where you might need to basically delete a virtual machine (VM) , keep its OSDisk and attach it to another Linux VM where you can then repair whatever is wrong on that old VM, however in some instances you would also be able to have network access and some way… Read more

Best Practices: Using SSH keys to access Linux VMs on Azure

When deploying Linux workloads on Azure, Microsoft highly recommends using SSH keys since they provide a more secure way of logging on to a Linux instance using SSH than using normal passwords. Most of the time passwords can be cracked with for example a brute force attack whereas SSH keys are nearly impossible to decipher… Read more

Best Practices: Running Linux on Azure

A lot of times we help customers getting the best out of running their workloads on Azure using any of our Endorsed Linux Distributions. There are a few best practices and recommendations that will sure help getting the most out of your Linux virtual machines and we would like to share a few of them. A… Read more

Azure PowerShell: How to delete and re-deploy a VM from VHD

Before moving further, please make sure you have Azure PowerShell installed: How to install and configure Azure PowerShell For basic information about using Azure Powershell with Resource Manager (ARM), please have a look at: Using Azure PowerShell with Azure Resource Manager In this example, the following variables are being used: Resource Group: ARMGROUP Original VM… Read more

Azure CLI: How to delete and re-deploy a VM from VHD

Before moving further, please, make sure you have the Azure CLI tools installed: Install the Azure CLI For the steps to work properly, please, make sure you are logged in to the Azure CLI: Connect to an Azure subscription from the Azure Command-Line Interface (Azure CLI) For basic Azure CLI commands in Resource Manager (ARM),… Read more

Linux Recovery: Cannot SSH to Linux VM due to FSTAB errors.

There are a few cases where a VM might stop booting up properly if the syntax in fstab is not correct and also if a data disk is missing (not attached to the VM) as well as other reasons. Traditionally in Linux you can mount a scsi device by using the following format in fstab:… Read more