Azure - SSH troubleshooting

About

When you can't connect to your machine via SSH.

Steps

The documentation

• Go to the Azure Portal
• Select your machine
• Select “Diagnose and solve problems”
• Wait a little bit
• Select “I can't connect to my Linux VM”

The VM is running ?

Verify if your VM is running by viewing your VM's console screenshot or logs.

Boot diagnostic

• Enable the Boot Diagnostics. (Vm> Support + Troubleshooting sub-header > Boot Diagnostic > Diagnostic Settings)

• Restart the machine
• Check the log. Review errors in the logs such as:
  • FSTAB (file systems table),
  • FSCK (file system consistency),
  • or networking

Review effective security group rules

Reset Ssh Configuration

• Azure portal > Support + Troubleshooting section > Reset password
• Or with the Azure Cli
  • Create the file reset_sshd.json

{
    "reset_ssh":"True"
}

• Execute the following command

az.cmd vm extension set \
  --resource-group resourceGroupName \
  --vm-name vmName \
  --name VMAccessForLinux \
  --publisher Microsoft.OSTCExtensions \
  --version 1.4 \
  --protected-settings reset_sshd.json

Redeploy

Address any Azure host issues by redeploying, which will migrate the VM to a new Azure host

Documentation / Reference

• How to reset a Linux VM password or SSH key, fix the SSH configuration, and check disk consistency using the VMAccess extension
• Manage administrative users, SSH, and check or repair disks on Linux VMs using the VMAccess Extension with the Azure CLI 2.0 - Good one !