CAEDM groups

CAEDM groups are used for class assignments, clubs, research, department files, and more.

CAEDM groups can be created and used by anyone with a CAEDM account. Each group has users and resources available to be added to the group. Groups are one of the many collaboration resources made available by the college through CAEDM.

Group User Rights

Group User Rights Venn Diagram. Note the separation of the Management Responsibility and File Access Rights

Group rights and responsibilities are divided between Management Responsibilities and Access Rights. The Group Owner (and optional Group Managers) handle Management Responsibilities, while Group Members have Access Rights. These responsibilities and rights are further detailed in the following subsections.

Group Owner

The Group Owner has ultimate Management Responsibility of the group. These responsibilities include:

NOTE: Group Owner DOES NOT imply Group Member!  The Group Owner WILL NOT have File Access UNTIL the owner is added to the list of Group Members.

Group Manager

A Group Owner may need help managing a group's membership on occasion. To that end, a Group Owner may designate a list of Group Managers to assist with Group Membership Management.

For example, an Instructor may ask TAs to add a class' students to the class group each semester, or ask a research lead to do the same for their research groups. A club president might delegate membership duties to a club secretary or other officer. A faculty might delegate membership changes of a college group to department secretaries, a CSR, or to someone in a collaborating college department.

In short a Group Manager manages group file and resource access by:

NOTE: A Group Manager is NOT NECESSARILY a Group Member!  A Group Manager WILL NOT have File Access UNTIL the group manager is added to the list of Group Members.

Group Members

Group Members are the heart and soul of a group, and they have Access Rights to the files and resources of the group.

  • Full-Access Members have:
    • read/write Access Rights to the group's files,
    • complete Access Rights to any other group resources
  • Read-Only Members have:
    • read-only Access Rights to the group's files,
    • complete Access Rights to any other group resources

Default Group Resources

Video: CAEDM Groups

Group Filespace

By default, each group is given a generous amount of filespace to share. Files created in a group space can be edited and deleted by any full-access member. Read-only members will be able to read and copy files from this filespace. Changes made to files on a group space affect other users. Keep this in mind when deleting files that others may still be interested in.

There is a quota, or limit to the number of gigabytes, you can store on your group filespace. Group quotas do not count against personal filespace quotas.

To access group files:

From Windows

  • Go to J:\groups.
  • Click on the folder with your group's name.

From Linux

  • Go to $HOME/groups.
  • Click or cd into the folder with your group's name.
WARNING: DO NOT DELETE YOUR 'groups' FOLDER OR ANY OTHER <groupname> FOLDER THEREIN!!! The groups folder is a container for all of your groups.  If you delete the groups folder, your operating system may systematically delete every file in every group you are a member of.  This could potentially affect many other students, faculty and staff.

The 'groups' folder is managed automatically based on your group membership. Please do not delete the 'groups' folder, delete groups in the 'groups' folder, rename or move any group in the 'groups' folder, or put any other file or folder in the 'groups' folder. Doing so is just asking for trouble.

CAEDM GENERAL WARNING: Modifying your 'groups' folder has been known to cause problems in any state of mind you happen to be.  These problems may cause secondary symptoms including, but certainly not limited to, mild-to-severe headaches, elevated heart rates, failing grades, abandoned research, forked working trees, sleepless nights, delayed-restoration anxiety, and generally-strained-interpersonal-relationship syndromes.

Fast Space

Fast Space, as the name implies, uses high-speed, enterprise-grade hard disk drives that can handle reading and writing small, scattered chunks of data continuously for an extended period of time. While high-performance disks are significantly faster than a disk you might buy at a retail store, they don't hold nearly as much data. For this reason, the quotas are smaller.

Fast Space works best for highly-random workloads, such as group projects for classes, small data sets that are actively read and written, compiling source code, rendering models, presentations, documents, spreadsheets, small videos, images, etc.

Big Space

Big Space uses enterprise-grade disks that are much larger, and the quotas are also much larger. The downside is the disks are slower, providing roughly the same performance as a common disk you would buy at a retail store.

Big Space is best for large streaming workloads and large data sets that are referred to periodically, but not on an active, continuous basis. Examples of streaming workloads would include reviewing the results from finite element analysis, batch results, simulations, data sampled from lab equipment during an experiment, video clips of student projects or capstone projects, large image repositories, etc. Large numbers of smaller files such as office suite documents are also welcome to be stored in Big Space groups, just keep in mind that the disks are larger and slower than Fast Space. The more serialized your workload is the better.

If you decide to use big space for your group and the need arises later to reprocess or compute against that data, you can still add Scratch Space to the group and temporarily copy the relevant data sets to that high-performance Scratch Space area. Any final results from the processing can be written back to Big Space if done so in a streaming fashion, or copied from Scratch Space to Big Space when the results are complete.

Group Web Space

Every group file space is created with a www folder. Files placed in this folder are published to the web at Group web spaces are subject to group quota limits and have all of the same resources and limitations as user webspaces.

Secure Web Space

Group websites can also be accessed through HTTPS. All group spaces have a security certificate that they share to allow secure connections. To access a group webspace over HTTPS, use the url

Some web frameworks may have a configuration option to automatically redirect the client to HTTPS. If your framework does not, it may also be possible to use mod_rewrite rules in an .htaccess file to dynamically force all requests to use HTTPS, but be aware that your site will take a performance hit when doing so.

Optional Group Resources

Scratch Space

Scratch Space has no quota, but is not backed up.
Scratch Space gives groups a temporary location to store large files, such as checkpoint files, large dataset lookups, intermediate render results, etc. Fifteen minutes after enabling Scratch Space for a group, the system will create a 'scratch' directory in that group's directory.

Unlike the standard J Drive, or a group filespace, Scratch Space does not have an enforced quota. Files in the 'scratch' directory are stored in a separate storage system, and will not count against your Fast/Big Space group's quota.

Scratch Space is intended to be a temporary location for data. Files placed in Scratch Space are not backed up. So please, write your final results somewhere else, outside of the 'scratch' directory. Do not store anything in Scratch Space that you cannot replace or regenerate easily.

The Scratch Space storage system has been designed for fast random read/write speeds. For such workloads, Scratch Space will be slightly faster than Fast Space group storage, and significantly faster than Big Space group storage.

Scratch Space is a pooled resource. When the community pool fills to near capacity, the oldest files in the space are deleted to clear the dead wood and allow for new, temporary storage. The storage space itself is many terabytes in size and typically does not cycle very often. That said, please use the space responsibly and clean up after yourself.

Important Scratch Space Facts

  • There is no quota
  • Files are not backed up
  • Is temporary storage, particularly useful for FEA, CFD, rendering, large dataset lookups, etc
  • Faster random read/write than Fast/Big Space group storage
  • Is accessible at:
    • J:\groups\group_name\scratch\ on Windows
    • ~/groups/group_name/scratch/ on Linux
  • You need to wait 15 minutes for scratch space to appear after enabling it

How to Add Scratch Space

Use the CAEDM website as outlined below, to modify a group to have scratch space.

Group Printing

Group printing may be useful for departments and other groups, enabling students to print using common funds.
Group printing provides a method for any user in a CAEDM group, with group printing enabled, to charge printing costs of selected jobs to specific group print accounts. For example, a student employee could print a document for a professor in the CAEDM lab, and the professor's department account would directly cover the cost of the print job.

Enabling Group Printing

To set up this feature, you will first need an existing CAEDM group. Even if the sole purpose of the group will be to share printing costs, all of the default group resources need to be created for this group. After the CAEDM group has been created, a Full-Time CAEDM employee can add the print feature to your group account. You will need to provide a journal entry from your department or research group to initiate a balance on your account. A professor or department secretary can help you with a journal entry. You will need to decide how much money you would like to pre-load onto your group print balance. Contact a CAEDM employee to have this feature enabled.

How to use Group Printing

To print using a CAEDM group account balance, print as normal and select "Charge a group account" on the CAEDM Print Driver dialog. For instance, if a student wanted to print to ctb450psa, using a group print balance, they would print to CAEDM and select "ctb450psa" + "Charge a group account".

After the job is sent to the printer, you need to release the print job. This step is necessary to authorize the use of group funds, and to select which group will pay for the desired print.

To release a print job:

  • Login into and follow the menu: Printing->Release Print Job.
  • Find the job you just sent to the group queue, and release the job.
  • If enough money is in your group account to print the job, the job will print immediately to the printer you chose.

Group Database

A group may request a MySQL database. The database must be for legitimate academic purposes related to the college. Click here for database creation instructions.

Group Management Instructions

General Notes on Group Changes

Most changes to a group's memberships and resources require 15 minutes to take full effect. Also, any existing connection a new group member has with the fileservers will need to be restarted before that member can access your group. Please keep these two items in mind, especially when creating groups and when adding new members. Otherwise your new group members will get an "Access Denied" error message when opening your group's directory.

To refresh your connection's group memberships:

  • On Windows:
    1. Wait 15 minutes after the change is submitted
    2. Log out of your computer and back in again, or log in on a different machine.
      • Alternatively, you can unmap and remap the J Drive, if you prefer.
  • On a CAEDM Linux machine:
    1. Wait 15 minutes after the change is submitted
    2. Log out of your computer and back in again.
      • Alternatively:
        1. Run "su - $USER" at a command prompt
        2. Login as if this were a new terminal login
          • A new login process will be started, group memberships are then re-established, and any new process you start from this login terminal will have your new group memberships. This will not, however, affect existing processes or their new subprocesses.

If after the 15 minute wait time and the subsequent reconnection a group member is unable to use the group, please contact a CAEDM administrator for help.

Creating a Group

When you create a group, you become it's owner. There are some responsibilities that only an owner can perform, such as transferring group ownership to a new owner, or adding optional group resources to the group.

When a group is created, it will come with all of the default group resources. The owner may add optional resources later.

Note that owners and managers will also need to be added to the members list if they wish to use the group's filespace.

Each CAEDM user is limited in the number of groups that they may create. This number depends on the circumstances of the account; faculty, staff and students may have different allowances as to the number of groups that they are authorized to create.

To create a group:

  1. From the CAEDM website, select "Create a Group" from the Groups menu.
  2. Follow the detailed instructions on the "Create a Group" webpage.
  3. Wait 15 minutes for the group to be created.
  4. Dis/re-connect to the fileserver. This can be done by logging off and back on your machine, or disconnect and reconnecting to your J-drive.

Deleting a Group

Deleting a group makes resources available for other users. If you are done with the resources in your group, delete it. It is good practice to make sure the members of the group are finished with shared resources before you delete the group. To delete a group:

  1. From the CAEDM website, select "Manage My Groups" from the Groups menu
  2. Click the "Delete groupname" button for the group you wish to delete.

Additional Quota

It may be possible to request more filespace for your group. See Quota Extensions for more details.

Modifying a Group

Group Owners can view and configure most group features from the Groups menu of the CAEDM website. Some features, like adding a database to a group and group printing, must be enabled by a CAEDM Administrator before they can be configured and used. Group Managers can manage group membership from the same Groups menu of the CAEDM website.

Renewing a Group

Renewing a group will allow the group to exist for another few months to a year. The exact timeframe depends on who owns the group. For example, groups owned by faculty are not renewed as often as groups owned by undergraduate students. To renew a group:

  1. From the CAEDM website, select "Manage My Groups" from the Groups menu
  2. Click the "modify" button of the group you wish to renew.
  3. Click the "Renew this group" button

Transferring ownership of a Group

When an owner of a group leaves the university, groups that user owns will need to be given to another user. It is best practice to complete this process before the group owner retires or graduates, etc. Finding an owner of a group becomes more difficult once they have left the university. To give a group away:

  1. From the CAEDM website, select "Manage My Groups" from the Groups menu
  2. Click the "modify" button of the group you wish to renew.
  3. Click the "Give Group to Someone Else" button

Editing Group Members

Owners and managers may manually add and remove both full access and read-only members to a group. Members may also be Auto Populated by class section.

To Edit Group Members:

  1. From the CAEDM website, select "Manage My Groups" from the Groups menu
  2. Click the "modify" button of the group you wish to edit membership of.
  3. Click the "Edit Members" icon in the left sidebar.
  4. Follow the detailed instructions on the Edit Group Membership webpage.
  5. Allow 15 minutes for group membership changes to take effect.
  6. If you added group members, ask them to log out of and back into their computer.

Editing Group Managers

A group owner may delegate adding and removing users from a group to group managers. This feature may be useful to delegating this responsibility to department employees or research assistants. To Edit the List of Group Managers:

  1. From the CAEDM website, select "Manage My Groups" from the Groups menu
  2. Click the "modify" button of the group you wish to edit managers of.
  3. Click the "Edit Managers" icon in the left sidebar.
  4. Follow the detailed instructions on the Edit Group Managers webpage.

Auto Populating a Group

This feature is available to users who are involved in teaching coursework. Auto Populate Courses adds and removes membership in a group based on enrollment in specified class sections. Group membership may change daily as people add and drop classes. A group may have a combination of manually added members and Auto Populated members. To use this feature:

  1. From the CAEDM website, select "Manage My Groups" from the Groups menu
  2. Click the "modify" button of the group you wish to Auto Populate.
  3. Click the 'Autopopulate" icon in the left sidebar.
  4. Follow the detailed instructions on the Auto Populate webpage.

Adding Scratch Space

Group managers or owners can use the CAEDM website to add scratch space for a particular group. After adding the scratch space, it may take up to 15 minutes for it to be created.

  1. From the CAEDM website, select "Manage My Groups" from the Groups menu
  2. Under the section, "You are the owner of the following groups" click on the button "Modify -groupname-".
  3. Scroll down and look for the option to "Create" scratch space. Select it and click the button to submit the changes for the group.
  4. Within the next 15 minutes a folder called scratch will be linked in your groups' group folder -homedir-/groups/-groupname-/scratch
  5. In this folder you can store temporary files.
  6. Be sure to save irreplaceable files elsewhere, since all files left in scratch will eventually be removed.