OpenSSH Fails Silently: No Output from ssh-V, Exit Code 127

When attempting to check the OpenSSH version using the ssh-V, ssh-v, ssh-vv, ssh-vvv, or ssh-vvvv command in Bash 5.2.21, you may encounter a situation where no output is displayed, and the exit code is 127. This article will discuss the possible reasons for this issue and provide solutions.

Understanding the Problem

The ssh-V command is used to check the version of OpenSSH installed on a system. However, when it fails silently, it can be challenging to identify the cause of the problem. Exit code 127 usually indicates that the command is not found or that there is a problem with the command syntax.

Possible Reasons for the Issue

There could be several reasons for the failure of the ssh-V command with exit code 127, including:

• The OpenSSH client is not installed on the system.
• The OpenSSH client is installed, but it is not in the system's PATH.
• The ssh-V command is not a valid command for checking the OpenSSH version.

Solutions for the Issue

To resolve the issue of the ssh-V command failing silently with exit code 127, follow the solutions below:

Installing OpenSSH Client

Ensure that the OpenSSH client is installed on the system. If not, install it using the package manager of your operating system. For instance, on Ubuntu or Debian, you can use the following command:

Adding OpenSSH Client to PATH

If the OpenSSH client is installed but not in the system's PATH, you can add it manually. To do this, first, identify the installation directory of the OpenSSH client. Then, add the directory to the PATH environment variable.

Checking OpenSSH Version

Instead of using the ssh-V command, you can check the OpenSSH version using the ssh command with the -V flag. For example, the following command will output the OpenSSH version:

Conclusion and References

In summary, when checking the OpenSSH version using the ssh-V command fails silently with exit code 127, it is usually because the OpenSSH client is not installed or not in the system's PATH. The recommended solution is to install the OpenSSH client or add it to the PATH environment variable. Alternatively, you can use the ssh command with the -V flag.

• ssh man page
• Debian OpenSSH wiki
• OpenSSH homepage