You cannot connect to an Azure Linux virtual machine (VM) by using Secure Shell (SSH). When you run the Boot Diagnostics feature on Azure portal, you see log entries that resemble the following examples.
Examples
The ssh daemon in Red Hat Enterprise Linux uses the configuration file /etc/ssh/sshdconfig. The daemon is set by default to accept both SSH protocol versions 2 and 1, and has an entry in the configuration file: # Protocol 2,1 To force the. Checks if an SSH server supports the obsolete and less secure SSH Protocol Version 1. Nmap -sV -sC Script Output PORT STATE SERVICE 22/tcp open ssh sshv1: Server supports SSHv1 Requires. Nmap; shortport; string; Author: Brandon Enright. At this point, the SSH extension has connected to your Raspberry Pi and is asking you to verify that the host key The SSH extension is designed to be secure, and because of this goal, it needs to identify that the computer you're trying to connect to is actually the computer you expect. To make this job easier, the computers generate a long.
The following are examples of possible errors. Assetsgenerator.
Example 1
Example 2
Cisco Ssh Version 2
- At this point, the SSH extension has connected to your Raspberry Pi and is asking you to verify that the host key The SSH extension is designed to be secure, and because of this goal, it needs to identify that the computer you're trying to connect to is actually the computer you expect. To make this job easier, the computers generate a long.
- If you want to downgrade to Ooly sshv1 (ip ssh version 1) the software will be upgraded/donwgraded from 1.99/2.0 1.5. If you want to go back to version 1.99 of.
Example 3
Example 4
This example is caused by a clean fsck. In this case, there are also additional data disks attached to the VM (/dev/sdc1 and /dev/sde1).
This problem may occur if the file system was not shut down cleanly or storage related issues. The issues include hardware or software errors, issues with drivers or programs, write errors, etc. It is always important to have a backup of critical data. The tools that describe in this article may help recover file systems, but it is data loss can still occur.
Linux has several file system checkers available. The most common for the distributions in Azure are: FSCK, E2FSCK, and Xfs_repair.
Resolution
To resolve this problem, boot the VM into emergency mode by using the serial console and use that tool to repair the file system. If the serial console is not enabled on your VM or doesn't work, see the Repair the VM offline section of this article.
Use the serial console
Ssh Use V1
Connect to the serial console.
Note
For more information about using serial console for Linux, see:
Select the Power icon button, and then select Restart VM. (If the serial console is not enabled or not connected successfully, you won't see the button.)
Boot the VM in to emergency mode.
Enter the password of your root account to sign in to emergency mode.
Use xfs_repair with the -n option to detect the errors in the file system. In the following sample, we assume that the system partition is /dev/sda1. Replace it with the appropriate value for your VM:
Run the following command to repair the file system:
If you receive the error message 'ERROR: The filesystem has valuable metadata changes in a log which needs to be replayed', create a temporary directory and mount the filesystem:
If the disk fails to mount, run the xfs_repair command with the -L option (force log zeroing):
Next, try to mount the file system. If the disk is mounted successfully, you will receive the following output:
Restart the VM, and then check if the problem is resolved.
Repair the VM offline
Ssh V1
Attach the system disk of the VM as a data disk to a recovery VM (any working Linux VM). To do this, you can use CLI commands or you can automate setting up the recovery VM using the VM repair commands.
Locate the drive label of the system disk that you attached. In this case, we assume that the label of the system disk that you attached is /dev/sdc1. Replace it with the appropriate value for your VM.
Use xfs_repair with the -n option to detect the errors in the file system.
Run the following command to repair the file system:
If you receive the error message 'ERROR: The filesystem has valuable metadata changes in a log which needs to be replayed', create a temporary directory and mount the filesystem:
If the disk fails to mount, run the xfs_repair command with the -L option (force log zeroing):
Next, try to mount the file system. If the disk is mounted successfully, you will receive the following output:
Unmount and detach the original virtual hard disk, and then create a VM from the original system disk. To do this, you can use CLI commands or the VM repair commands if you used them to create the recovery VM.
Check if the problem is resolved.
Ssh V1 Vs V2
Next steps