The IU Massive Data Storage Service (MDSS) is accessible using a couple different mechanisms.

• Accessing MDSS via a Web Browser (MDSSWeb)

  You can use the web interface by just going to https://www.mdss.iu.edu/. See the MDSSWeb Knowledge Base Article for more details.

• Accessing MDSS via HSI

  The Hierarchical Storage Interface (HSI) Software is installed on the CS unix systems and can be used to access the MDSS. To use this software, just run hsi and you should be prompted for a "Principal", which is just your username. Then you'll be prompted for your password.

  Once you are logged in, you are ready to issue hsi commands. You can just run help to get a list of commands or see the HSI KB entry for more information. Hsi is similar to ftp but gives you much more flexibilty with the ability to do things you can do from a shell, such as moving, copying, and renaming files and using wildcards.

  The KB Article on HSI provides much more detailed information about how to use hsi. This page describes mechanisms for generating data via a pipe and storing it on MDSS as well as a discussion on alternate authentication mechanisms. Be sure and pay close attention to the Class of Service you are using and take note of the Related KB Article so your large backups do not fail.

  Here is an example showing how you can use tar on the local CS system and save the output to MDSS using hsi:

  cd /some/directory
  hsi 'put cos=3 copies=2 coslist-large "|tar cf - ." : some_directory.tar'

• Accessing MDSS via HTAR

  The HSI package also includes htar which provides a convenient way to read and write tar archives to the MDSS. It behaves just like the normal tar command but read and writes tar archive files to and from MDSS. For example, you can create a tar archive of some directory with:

  htar cf archive.tar some_directory

  The resulting tar file, archive.tar, will be written to MDSS. Similarly, you can extract files from a tar file on MDSS with:

  htar xf archive.tar

  Each time you run htar you will be prompted for your username (aka. Principal) and password.

  As with hsi, see the The KB Article on HSI for information on alternate authentication methods available with htar.

• Accessing MDSS via SFTP or SCP

  You can use standard SSH clients to access MDSS using the hostname sftp.mdss.iu.edu. See the Associated KB Entry for details.

• Accessing MDSS via PFTP

  You can access MDSS using pftp as follows:

  1. Obtain a kerberos ticket by running kinit. On the CS linux machines the kerberbos binaries are in /usr/kerberos/bin so you should be sure this is in your path. This should be in your path by default for CS accounts but you may need to add this if you explicitly set your path. When you run kinit you will be prompted for your IU kerberos password.

  2. Connect to hpss.iu.edu:

     pftp hpss.iu.edu

     If you get an error like this:

     init_sec_context: (krb5) Miscellaneous failure: No credentials cache found

     then this probably means that you didn't load your kerberos ticket before running pftp. Please run kinit to load your ticket.

     If you don't see the credentials error but are still prompted for a password like this:

     Name (hpss.iu.edu:usename):

     then this probably means you are using the wrong version of pftp. Note that there is the standard linux ftp client (/usr/bin/pftp) and the pftp client for use with HPSS (/usr/local/bin/pftp) on the system so check which version you are using.

     When this all works properly, you should be automatically logged into HPSS when you issues the pftp command.

  Please see the Associated Knowledge Base Entry for further details about using pftp.

Anyone interested in using the MDSS is encouraged to check out the MDSS Starter Page for more information.

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