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Teleport is software which provides an SSH Jump Host (or Bastion host) service in a secure, modern way, with support for role-based access control and single sign-on. It is a replacement for the ecAccess SSH service, and is operated by the CD Apps team and User Services.

Warning

This service is feature complete, but not fully operational (it is not monitored).
ecAccess will continue to run in Shinfield, and this service only will be deployed in Bologna.

Tip

Visit the Teams channel for this service to discuss and provide feedback!

Table of Contents
maxLevel1

Overview

The Teleport used to access a number of services at ECMWF, including our Atos HPCF and ECS services. The service provides:

  • Single SSH hop from client systems anywhere on the internet to servers inside ECMWF (ecGate, HPC, etc)
  • Re-authentication required only every 12 hours (usually once per working day)
  • Integration with standard tools such as the OpenSSH ssh client, scp, and ssh-agentWeb-SSH interface for in-browser terminal access, with scp
  • X11 and Port forwarding

The single sign-on step is performed using an application called "tsh", every 12 hours.After . After that you use standard ssh or scp to connect to systems inside ECMWF.

Alternatively you can have simple Gravitational Teleport

Downloading tsh 

The tsh application is required to perform user authentication once every 12 hours.

tsh is open source, very portable, and has minimal dependencies.

The binary is available for Linux 32-bit, 64-bit, and ARM, as well as Windows 64-bit and a signed package for MacOS.

MacOS users can also use homebrew for installation (brew install teleport).

User Authentication

Once every 12 hours, you will need to refresh your tokens by logging in to the ECMWF website.

Info

SSH connections can remain active for longer than 12 hours, but new ones will require re-authentication.

First Time

Run tsh, giving the location of our gateway:

Code Block
languagebash
themeMidnight
tsh login --proxy=shell.ecmwf.int:443

Your default web browser will open and you should login with your email address, workstation password, and then HID Token code.

Info

If you're already logged in to the ECMWF website, or have recently logged in to this service, the password prompt might be skipped.

Subsequent Occasions

Code Block
languagebash
themeMidnight
tsh login

Connecting to hosts through the gateway

Info

Windows users should skip to our Guide for Windows SSH to ECMWF.

OpenSSH 7.3 or later has a simple command line option to connect via our gateway (shell.ecmwf.int) to the destination-host:

Code Block
languageyml
ssh -J username@shell.ecmwf.int username@destination-host

For example, if your username is ab0 and you wish to connect to ecgate:

Code Block
languagebash
themeMidnight
ssh -J ab0@shell.ecmwf.int ab0@ecgate

The OpenSSH configuration setting for this is named ProxyJump:

Code Block
languagebash
Host ecgate
  User ab0
  ProxyJump ab0@shell.ecmwf.int

See the Legacy Configuration note below if your ssh client is older than 7.3.

If your connection fails after working for some time, it could be because your tokens have expired. You can check them:

Code Block
languagebash
$ tsh status
> Profile URL:  https://shell.ecmwf.int:443
  Logged in as: firstname.lastname@ecmwf.int
  Cluster:      shell.ecmwf.int
  Roles:        *
  Logins:       ab0
  Valid until:  2020-06-22 23:26:30 +0100 BST [EXPIRED]
  Extensions:   permit-X11-forwarding, permit-agent-forwarding, permit-port-forwarding, permit-pty

Destination Hosts available

The hosts directly available through the Teleport gateway are:

  • Linux VDI (both legacy OpenSUSE and CENTOS 8 beta)
  • Physical office workstations
  • ecGate
  • HPC2020 TEMS

To access any other host, the ProxyJump feature allows chaining by using a comma, like so:

Code Block
languagebash
ssh -J ab0@shell.ecmwf.int,ab0@workstation ab0@lxc

Configuring password-less login

Tip

The CENTOS 8 Linux VDI beta service already supports automatic password-less login - you can skip this procedure.

With the initial configuration you may be prompted for a password at the destination-host.

Add the Teleport certificate authority to your ~/.ssh/authorized_keys file:

Code Block
languagebash
themeMidnight
curl -fs https://nexus.ecmwf.int/repository/internal-teleport-configs/prod/teleport_user_ca.pub >> ~/.ssh/authorized_keys
Info

This configuration will allow access to any host which mounts the same $HOME directory. 

Terminal Access in a Web Browser

You can open a tabbed terminal in the web browser, with support for SCP upload and download.

Info

It will only work if you have set up password-less login (which is automatically done for you on CENTOS 8 Linux VDI beta).

Browse to http://webshell.ecmwf.int/destination-host/username  (replacing destination-host and username with your selection).

For example, if your username is ab0 and you wish to connect to ecgate:

Code Block
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http://webshell.ecmwf.int/ecgate/ab0
Info

The destination host should be just the short name, without "ecmwf.int".

If you open another tab inside the web terminal, use the QUICK LAUNCH box and enter "username@destination-host:22", for example ab0@ecgate:22.

Tip

The web terminal works very well to access tmux or screen running on the destination host!

Windows Clients

There are various ways to initiate SSH from Windows 10, so it depends on your system and your preferences.

Tip

We recommend using the Windows Subsystem for Linux if you can (on your own machine), followed by starting the SSH Agent and then connecting as for Linux/MacOS systems.

...

titleMobaXterm SSH from Windows 10 (ECMWF laptop)
  1. Install MobaXterm if it is not already on your system
  2. Download tsh (you may need to instruct antivirus software to ignore the file)
  3. Start MobaXterm
  4. Login using tsh (you will always need to specify the --proxy setting)
  5. Use the following in $HOME/.ssh/config (MobaXterm's home):
Code Block
languagebash
Host ecgate
  User ab0
  ProxyCommand ssh -q -i c:/users/ab0/.tsh/keys/shell.ecmwf.int/firstname.lastname@ecmwf.int -W %h:%p ab0@shell.ecmwf.int
  IdentityFile c:/users/ab0/.tsh/keys/shell.ecmwf.int/firstname.lastname@ecmwf.int

...

titleNative SSH from Windows 10 (own machine)
  1. Start the Windows SSH Agent Service
  2. Download tsh (you may need to instruct antivirus software to ignore the file)
  3. Login using tsh (you will always need to specify the --proxy setting)
  4. Use an SSH config as below:
Code Block
languagebash
# Windows currently has a bug, you need the full path to ssh or you will get:
# posix_spawn: No such file or directory

Host *.ecmwf.int
  User ab0
  ProxyCommand C:\Windows\System32\OpenSSH\ssh.exe -q -W %h:%p ab0@shell.ecmwf.int

# this assumes the SSH Agent is running, otherwise add:
# Host shell.ecmwf.int
#   IdentityFile ~/.tsh/keys/shell.ecmwf.int/firstname.lastname@ecmwf.int

...

The Windows 10 Terminal is a decent tabbed command line interface (albeit with no X11 support).

Here are the instructions on how to set it up depending on your platform:

Info
titleSystem Administrators

If you are a system administrator setting up access to teleport from your organisation, have a look at the Teleport SSH Access - Network requirements for additional information on how this system works and its network requirements.


Warning

Please be aware that you must use a version of "tsh" equal to or lower than 13. We are working on removing this limitation in the very near future

...

titleNew sessions can be configured following this example
Code Block
languagejs
{
  "guid": "{717406b0-06cb-454c-a0c4-875267fa373d}", # run "[guid]::NewGuid()" in a PowerShell to generate this
  "name": "ecGate",
  "commandline": "ssh ab0@ecgate.ecmwf.int"
  "suppressApplicationTitle": true,
  "hidden": false,
  "fontSize": 10,
  "fontFace": "Fira Code",
  "cursorShape": "filledBox",
  "cursorColor": "#073642",
  "colorScheme": "Solarized Dark",
},

Other Notes

SSH Agent is required

If you have logged in but ssh fails to connect, it may be that your SSH agent is not running.

The Agent can be started and tokens refreshed this way:

Code Block
languagebash
eval $(ssh-agent -s)
tsh logout
tsh login

And this will make sure the Agent continues to run in your environment:

Code Block
languagebash
echo 'eval $(ssh-agent -s)' >> ~/.bash_profile

SCP, X11, Agent, and Port Forwarding

SCP, Agent forwarding, X11 forwarding, and Port forwarding (including SOCKS proxy), all work through the Teleport gateway.

X11 under macOS

Code Block
languagebash
$ brew cask install xquartz
# start xquartz app
$ export DISPLAY=:0
$ ssh -X ....

Legacy Configuration

For OpenSSH clients older than 7.3, the following configuration can be used:

Code Block
languagebash
# ~/.ssh/config file:
Host ecgate
  User ab0
  ProxyCommand /usr/bin/ssh -q -W %h:%p ab0@shell.ecmwf.int

Difficult client environments

You might not be able to download and run tsh, or access our web login service, or run the SSH Agent, from where you wish to use ssh.

Instead you can use (or copy) the identity files which tsh stores in $HOME:

Code Block
languageyml
# ~/.ssh/config file:
Host ecgate
  User ab0
  IdentityFile ~/.tsh/keys/shell.ecmwf.int/firstname.lastname@ecmwf.int
  ProxyCommand /usr/bin/ssh -q -i ~/.tsh/keys/shell.ecmwf.int/firstname.lastname@ecmwf.int -W %h:%p ab0@shell.ecmwf.int

...