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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 Support.

Warning

This service is under development and not widely accessible. Please continue to use the existing ECAccess service!

Please read all the introductory "understanding" sections (even if you think you know them), so that the presentation of Teleport makes sense in context.

Table of Contents

Table of Contents

Warning

This service is under development and not widely accessible. Please continue to use the existing ECAccess SSH service.

Downloading tsh 

The tsh application is required to perform the single sign-on step once per day.

As tsh is written in Go, it is very portable and has minimal dependencies.

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

Initial login

Run tsh, giving the location of our Teleport gateway:

Code Block
languageyml
tsh login --proxy=tele.ecmwf.int
Tip

Subsequent logins can omit the --proxy argument, as this is cached in ~/.tsh/... files.

Your default web browser will open and you should login with your email address and token code workstation password.

Warning

The web login requires our workstation credentials, not the one-time password of ActivID tokens. This will be changed soon.

To see the credentials that tsh was given, their attributes and remaining lifetime, run:

Code Block
languageyml
$ tsh status
> Profile URL: https://tele.ecmwf.int:3080
  Logged in as: oliver.gorwits@ecmwf.int
  Cluster: tele
  Roles: *
  Logins: sy0
  Valid until: 2019-11-13 17:10:03 +0000 GMT [valid for 55m0s]
  Extensions: permit-X11-forwarding, permit-agent-forwarding, permit-port-forwarding, permit-pty
Note

During testing phase, we are only issuing one-hour credentials. Normally it would be for a working day.

Configuring servers and workstations for Teleport

At the destination host end, openssh needs to be configured to trust the SSH Certificate that your client is passing.

This can be done at the server level for all users, or by an individual user within their own account.

Info

If a user configures this for their own account, it will potentially allow access to any other system using the same $HOME filesystem.

A user can add the following to their ~/.ssh/authorized_keys file:

Code Block
languageyml
cert-authority ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDN85frMTtRzQaVjkHGM3NTOJD/5awWn2i1sAofzlO0PXM1jX/H+4zQKn1+ATUqU+TTU2v3V7fhZm0cWqRrofSLDVC80FkCFqzZRq2E4kMBP5sx4yf/mBKLzJ6luE8eV/3W0V6KEch5TV2ON8ltwFPWjB3D/puPU010UOJH/arlpW5h+n9dAtBCAtVuMYBEz/5uWcKcTJkFe2usQTVmpiEmt/yAx4LfLTFPs2+izLo+N3dBW92HFnKnQftZI5s8ysOENbKmxdWfcxdID5E91oneAvkmEKBeUutlYY3GV9621iuKnlEw6WF8wfQapdozzhSyb+LhqPDiBRotnerhA69/ clustername=tele&type=user

A server administrator can place the same key into /etc/ssh/teleport-user-ca.pub

They would then add the following to their /etc/ssh/sshd_config  file:

Code Block
AuthorizedKeysFile /etc/ssh/teleport-user-ca.pub .ssh/authorized_keys .ssh/authorized_keys2
Tip

Having a dedicated file for the trusted key means that it can easily be rotated using configuration automation.

Connecting to hosts through Teleport

Your ssh client will need to know about the Teleport gateway (proxy).

For OpenSSH 7.3 or newer, add the following to your configuration (~/.ssh/config):

Code Block
languageyml
Host ecmwf-hpcf
  HostName  hpcf-login.ecmwf.int
  ProxyJump tele.ecmwf.int:3023
  ForwardX11 yes

For OpenSSH clients up to 7.2, the following will work instead:

Code Block
languageyml
Host ecmwf-hpcf
  HostName hpcf-login.ecmwf.int
  ProxyCommand /usr/bin/ssh -q -p 3023 -W %h:%p tele.ecmwf.int
  ForwardX11 yes
Info

ecmwf-hpcf is merely a short alias and can be any name, including the target HostName.

Info

hpcf-login.ecmwf.int is the host name of whatever destination server or workstation you wish to reach.

Then, you can connect to the destination host:

Code Block
languageyml
ssh ecmwf-hpcf
Tip

No password will be required.

SCP, X11 and Port Forwarding

scp, X11, and port forwarding will all work through the Teleport gateway.

Of course, such features also need to be permitted on the destination server or workstation.

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 (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-agent
  • X11 and Port forwarding

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

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

Tip

See the AUTHORIZED_KEYS section of the sshd man page for how to configure restrictions on users coming via Teleport.