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EUMETSAT is establishing a new set of data access services that will bring the full data catalog online.  Some more information can be found here (in particular, see the part on the Data Store):

https://www.eumetsat.int/website/home/Data/DataDelivery/NewPilotDataServices/index.html

At the initial opening of EWC to users, these services were not yet fully tested, populated or widely-accessible.  Even once the services are open, it will still take time to fully populate them.

As a workaround for this intermediate period, virtual machines on the EUMETSAT cloud are able to mount an NFS share holding selected datasets.  This server will be maintained until it is no longer needed.


Mounting the EUMETSAT NFS data archive

Setting up your instance

For data access, you will need to provision your instance on the EUMETSAT cloud (or establish a VPN connection to the EUMETSAT cloud).

In order to mount the NFS drive, first, you need to create the Virtual Machine instances in the Morpheus UI. You can follow the Provision a new instance - web Knowledge Base Article to get started.

Mounting NFS Share

After logging in to the virtual machine that you want to access the EUMETSAT data, all you need is to do is mount the NFS drive that rests on 198.18.255.11 onto the directory where you want it.  You will need sudo permissions or root access to accomplish the major steps here.

  1. Verify access to the NFS server

    You can see all exported file systems on the EUMETSAT NFS server without mounting it using the showmount command like in the example below:

    karatosun@myfirstvm ~$ showmount --exports 198.18.255.11
Export list for 198.18.255.11:
...  (lot of text, but should include)
/ifs/data/EUMETSAT_DATA 
/ifs/data/EUMETCAST 
...

    If you receive an error (e.g. timeout), please refer to the troubleshooting section below.

  2.  Create the (empty) directory where you'll mount the NFS share

    You can place this anywhere you wish; we have chosen /eumetsatdata in the example here

    karatosun@myfirstvm ~$ sudo mkdir /eumetsatdata
karatosun@myfirstvm ~$ sudo echo "run sudo mount -a" > /eumetsatdata/NFS_NOT_MOUNTED  # put a placeholder file in the directory to make it clear what's (not) happened
karatosun@myfirstvm ~$ sudo chmod a+rX,go-w /eumetsatdata                             # minimise write permissions to prevent mistakes if the mount isn't there
    The last two commands add a little extra safety for the case that the directory is unexpectedly not mounted

  3. Mount NFS drive to the mount point

    This command will do a once-off mount.   If it works, you may wish to make it permanent as described in step 4

    karatosun@myfirstvm ~$ sudo mount 198.18.255.11:/ifs/data/EUMETSAT_DATA /eumetsatdata
    If you receive an error (e.g. timeout), please refer to the troubleshooting section below.

    If step 3 worked, you can now navigate to the /eumetsatdata directory and list all the available data with the ls -lah command

    [karatosun@myfirstvm ~]$ cd /eumetsatdata/
[karatosun@myfirstvm eumetsatdata]$ ls -lah
total 192K
drwxrwxrwx.  7 nobody   nobody   124 May 26 13:00 .
dr-xr-xr-x. 19 root     root     260 Jul  6 13:00 ..
drwxrwsr-x.  5     1002     1002 101 Nov  7  2018 eumetcast
drwxr-xr-x.  3 nobody   nobody    24 Apr 23  2018 mviri
drwxr-xr-x.  4 nobody   nobody    52 May 28 17:26 seviri
    Note that the ownerships and permissions will generally be "nobody"

  4. Making the NFS mount permanent and persistent across reboots (optional)

    Edit /etc/fstab file of the VM with your editor of choice

    karatosun@myfirstvm ~$ sudo nano /etc/fstab

    and add the following line

    198.18.255.11:/ifs/data/EUMETSAT_DATA /eumetsatdata nfs defaults 0 0

    A complete example of a /etc/fstab can be seen in the block below (do not copy all of this!)

    # /etc/fstab
# Created by anaconda on Thu Aug 8 12:37:33 2019
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
UUID=3ef2b806-efd7-4eef-aaa2 / xfs defaults 0 0

# mount the EUMETSAT NFS server to /eumetsatdata
198.18.255.11:/ifs/data/EUMETSAT_DATA /eumetsatdata nfs defaults 0 0

    To test the persistent configuration, unmount the share, then try to automatically remount it:

    karatosun@myfirstvm ~$ sudo umount /eumetsatdata
karatosun@myfirstvm ~$ sudo mount -a
    If you see an error and the manual mount worked previously, please check for typos!

Troubleshooting

Like all NFS mounts, if there is a problem accessing the server (networking issue, firewall, server down, server overloaded), this will cause attempts to access the mounted directory to freeze the process until the server returns.

Timeout/network connectivity: test that you can ping the NFS server with ping 198.18.255.11 command.  If not, you have a routing, firewalling or security group issue.  Assuming a default setup, the most likely issue is a security group problem.  Until we provide a knowledgebase article, please contact us.

Limitations

  1. Access to the archive is read-only.  This is a technical limitation due to the way the NFS server is mapped into the VM's address space.
  2. Only a limited subset of EUMETSAT data is available.  At the time of writing, this included Meteosat L1.5 data, a cloud type dataset and a few example files from EUMETCAST.  Please contact us if you need something that is not currently there.




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