hashicorp/vagrant · error · Vagrant::Errors::NetSSHException

An error occurred in the underlying SSH library that Vagrant

Error message

An error occurred in the underlying SSH library that Vagrant uses.
The error message is shown below. In many cases, errors from this
library are caused by ssh-agent issues. Try disabling your SSH
agent or removing some keys and try again.

If the problem persists, please report a bug to the net-ssh project.

%{message}

What it means

Error "An error occurred in the underlying SSH library that Vagrant uses. The error message is shown below. In many cases, errors from this library are caused by ssh-agent issues. Try disabling your SSH agent or removing some keys and try again. If the problem persists, please report a bug to the net-ssh project. %{message}" thrown in hashicorp/vagrant.

Source

Thrown at plugins/communicators/ssh/communicator.rb:575

          # This is raised if we failed to connect the max amount of times
          raise Vagrant::Errors::SSHConnectionRefused
        rescue Errno::ECONNRESET
          # This is raised if we failed to connect the max number of times
          # due to an ECONNRESET.
          raise Vagrant::Errors::SSHConnectionReset
        rescue Errno::ECONNABORTED
          # This is raised if we failed to connect the max number of times
          # due to an ECONNABORTED
          raise Vagrant::Errors::SSHConnectionAborted
        rescue Errno::EHOSTDOWN
          # This is raised if we get an ICMP DestinationUnknown error.
          raise Vagrant::Errors::SSHHostDown
        rescue Errno::EHOSTUNREACH, Errno::ENETUNREACH
          # This is raised if we can't work out how to route traffic.
          raise Vagrant::Errors::SSHNoRoute
        rescue Net::SSH::Exception => e
          # This is an internal error in Net::SSH
          raise Vagrant::Errors::NetSSHException, message: e.message
        rescue NotImplementedError
          # This is raised if a private key type that Net-SSH doesn't support
          # is used. Show a nicer error.
          raise Vagrant::Errors::SSHKeyTypeNotSupported
        end

        @connection          = connection
        @connection_ssh_info = ssh_info

        # Yield the connection that is ready to be used and
        # return the value of the block
        return yield connection if block_given?
      end

      # The shell wrapper command used in shell_execute defined by
      # the sudo and shell options.
      def shell_cmd(opts)
        sudo  = opts[:sudo]

View on GitHub (pinned to 35f3160f4a)

When it happens

Trigger: Thrown at plugins/communicators/ssh/communicator.rb:575 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of hashicorp/vagrant@35f3160f4a (2026-08-21). Data as JSON: /api/errors/749d8fd97ca6be81. Report an issue: GitHub.