Frequently Asked Questions

After your PI is granted an allocation, users can request accounts that must be approved by the Pi via email:
Please fill out the Request an Account form.
Any faculty member at Johns Hopkins University can request an allocation. All requests will be approved by the Dean’s office
Please fill out and Allocation Request form.
ssh -l userid
A two-factor authentication code is needed and a robust password
HOME Directory: 20 GBytes (/home/userid)
Lustre: 1 TByte per group (/scratch/users/userid and /scratch/groups/groupid)
data:    1 TByte per group
Storage can be increased up to 10TB per request from the PI

The Deans of the schools will make decisions on how to allocate resources.

Type the command “groups”.
Use the “interact” command and “interact -usage" for options.
HOME directories and “data”
To find out the group utilization the PI should use the command sbalance. It will give information about utilization by all members of the group.
For a summary of available partitions and their status, use the command sinfo -s
An email will be sent out to all users. Also, please check the website, HOME page.

DTNs are a set of dedicated nodes for file transfer. These servers are GlobusConnect end point and should be used to transfer large amounts of data.

  1. ssh (with your username and passwd)
  2. scp largefile.ext userid@your-destination
    Note that the speed is limited by the connectivity at your destination
  3. Form your machine to MARCC: scp largefile.ext
  4. Use the Globus connect end point
    1. Request a GlobusConnect account
    2. Login into your globus connect account
    3. Select the end points (MARCC)
    4. Authenticate to your end points
    5. Select the file(s) to transfer
    6. Start the file transfer

Users who need to run jobs immediately may be able to find out if resources are available. Use the command:
sinfo -s

A/I/O/T = Allocated/Idle/Out/Total

This research project (or part of this research project) was conducted using computational resources (and/or scientific computing services) at the Maryland Advanced Research Computing Center (MARCC).”

Please feel free to edit it and/or include more details.

  1. Download Filezilla  (Web search)
  2. Install Filezilla
  3. Launch Filezilla. Your local machine files and folders should be visible on the left side
  4. Click on the top left “icon” or click File-> Site Manager. A new window pops up
  5. Click on New site and name it “MARCC”
  6. Click on “General”
    1. Host: Port 22   (Type)
    2. Protocol: SFTP – SSH File Transfer Protocol   (select)
    3. Logon Type: Interactive (select)
    4. User: Your MARCC userid  (  (Type)
    5. Password: Leave blank (recommended)
  7. Click on “Transfer Settings”
    1. Select Limit number of simultaneous connections and set it to “1”
  8. Click on “Connect”
  9. You should be connected. MARCC files and Folders should be visible on the right side
  10. Click and Drag files/folders

That is it.