= Configuring pptransfer app and UM suite to pull data on `/work` from JASMIN =

The `pptransfer` task used to run on the ARCHER Data Transfer Node (dtn02) which we no longer have access to from February 19th. The instructions below modify a suite to run the `pptransfer` task on the JASMIN transfer nodes and pull the data across from ARCHER `/work` disk.

In the rose suite editor go to ''postproc -> Post processing - common settings’’:

 *  In panel ''Archer Archiving'' change '''archive_root_path''' to be a directory in your `$DATADIR` on  `/work` disk (e.g. `/work/n02/n02/ros/archive`.  This will be a temporary area to stage your data before transfer to JASMIN.

 * In panel ''JASMIN Transfer'' change '''transfer_type''' to '''Pull''' and '''remote_host''' to '''login.archer.ac.uk'''

In the `~/roses/<SUITEID>/site/archer.rc` file edit the section `[[PPTRANSFER_RESOURCE]]`:

 * Remove the line '''pre-script = "module load anaconda"'

 * Replace the  line '''host = dtn02.rdf.ac.uk''' with '''host = jasmin-xfer2.ceda.ac.uk'''

You now need to setup `ssh-agent` to be able to login to `jasmin-xfer2.ceda.ac.uk` and from there to `login.archer.ac.uk`.

== Setup required on PUMA and JASMIN ==

'''PUMA:'''

These instructions assume you already have an ssh-agent running on PUMA which you would already have needed in order to run a UM suite on ARCHER. 

* Log on to PUMA.

* Make sure you have a copy of your JASMIN ssh-key in your `~/.ssh` directory.  This is the key you generated when you applied for access to JASMIN. The remainder of the instructions assume it is called `id_dsa_jasmin` please replace this with the name of your key as appropriate.

* Setup `~/.ssh/config` file to login to the jasmin-xfer node. For example: 
{{{
Host jasmin-xfer2.ceda.ac.uk
Hostname jasmin-xfer2.ceda.ac.uk
User <jasmin-username>
IdentityFile ~/.ssh/id_dsa_jasmin
ForwardAgent no
}}}

  Replace `<jasmin-username>` with your JASMIN username.

* Run `ssh-add ~/.ssh/id_dsa_jasmin` to attach the key to your existing ssh-agent.

'''JASMIN:'''

1. Log on to JASMIN: `ssh jasmin-xfer2ceda.ac.uk` 

2. Setup PATH to Rose, Cylc and FCM:'''

* In your `~/.bash_profile` add the following:
{{{
if [[ `hostname` = "jasmin-cylc.ceda.ac.uk" ]]; then
  # Rose/cylc on jasmin-cylc
  export PATH=/apps/contrib/metomi/bin:$PATH
else
  # Rose/cylc on jasmin-xfer
  export PATH=/home/users/rshatcher/software/bin:$PATH 
fi
}}}

3. Setup ssh-agent to access ARCHER Login Nodes:

* Copy the private key you use on PUMA to access ARCHER over to JASMIN. This will be something like `~/.ssh/id_dsa`.
{{{
scp <puma-username>@puma.nerc.ac.uk:~/.ssh/id_dsa ~/.ssh
}}}

* Copy the ssh-agent start up script:
{{{
cp ~rshatcher/setup ~/.ssh
}}}

* In your `~/.bashrc` add the following to start up ssh-agent:
{{{
if [[ `hostname` = "jasmin-xfer2.ceda.ac.uk" ]] ; then
  # ssh-agent setup for transfer app
  . ~/.ssh/setup
fi
}}}

* In your `~/.ssh/config` add the following lines:
{{{
Host login.archer.ac.uk
  Hostname login.archer.ac.uk
  User <archer-username>
}}}

  Replacing `<archer-username` with your ARCHER username.

* Log out of `jasmin-xfer2` and back in again.

* Run `ssh-add`. You will be prompted for your passphrase.

Check that you can now ssh to ARCHER without prompt for password/passphrase by running: 

 `ssh login.archer.ac.uk`