Department of Computer ScienceGeneral problems & questions
For general problem reports please contact the Lab Staff. Please included detailed information on your problem, the more detailed, the better. Upon the receipt of the problem report, our automated problem queue will generate a unique problem ID and include this on the e-mail Subject line. The line will look similar to this:
Subject: Re: [Duke CS Request #20788] Can't send e-mail
Please make sure to keep this Subject: line in all follow-up messages concerning that specific problem.
If you have a question about how to set up your environment, how to use a program, how to etc..., please do not hesitate to send this to problem.
Opening/closing of CS accounts
CS accounts are separate from accounts provided by Duke OIT, and are generally restricted to faculty, students and staff having some close department affiliation. Accounts will be made available to qualifying persons or may be requested by contacting the Computer Science Lab Staff. More information about account availability and policies can be found in the Lab Accounts section of the web site.
Account closing are handled in a detailed, semi-automated manner; this is necessitated by the large number of undergraduate accounts in the department. Users receiving account closing notices should not panic, these notices are sent well in advance of any actual account closing and are intended to provoke a response from the account users. For more detailed information, please see the account closing policy page.
Changing your password
To change your password, run the following command at the UNIX/Linux command-line prompt:
passwd
You will be prompted for your current password, and then for your new password (you'll have to type the new one twice). If your new password isn't sufficiently obscure, it will be rejected.
Forgot your password?
If you have forgotten your password, please contact the Lab Staff. If you have just changed your password and have forgotten the new password, we usually can reset your password to the previous value. In all other cases we must reset your password to a new value. We are unable to tell you your password; they are stored in an encrypted form.
Note: we do not give out passwords over e-mail! We have no way of verifying user's identify over e-mail and it is insecure to have passwords stored in text messages. If you are not able to physically come by a lab staff member's office, please contact a faculty member of administrative staff by phone and we will relay your reset password through that person.
Checking group membership
You can check your group membership by using the UNIX/Linux groups command. Note that when you are added to a new group, you may need to login again for the new group membership to take effect.
You can check the membership of a particular group by using the getent command; for example, to find the users belonging to the group compsci330, you would use the following command:
% getent group compsci330.sp compsci330.sp*:6123:fred,jones % getent group | grep compsci330 compsci330.fa:*:6080:john,smith compsci330.sp:*:6123:fred,jones
where users fred and jones are the only members of this group. Note that this will not include group members who have the group ID as their primary group number in their password entry.
Group access to files
Department members make frequent use of UNIX groups to share files among group members. It is possible to set up shared directories such that all files created within the directory inherit the default group, (see the discussion about the group ID bit in the chmod man page), but it is up to the individual users to make sure the files have the proper permissions. This can either be handled manually, using the chmod command, as shown below:
% chmod g+w newfile
Alternatively, the user can affect all file creation permissions by changing their umask to 002 (the default is typically 022. Note if this method is chosen, this will affect all files created by the user!
Remote logins/Can't login to my desktop machine
If you are having trouble connecting to a department machine via ssh, please try connecting to login.cs.duke.edu first. Access to individual desktops is not guaranteed; these machines might be down for repairs or even be replaced entirely!
If you are experiencing problems logging into a known-available machine, particularly with the newer, Linux-based machines, you may have a problem with your account configuration files, or dot-files. For additional Linux/Unix information, please visit CSL: General and in the tabbed section following the bulleted list at the top, see the Linux/Unix tab (final tab).
Disk space and quotas
The Computer Science Lab provides ample disk space and quotas to store information for courses and research. We realize that at times users need more space for temporary storage. In events where short-term space is needed, please use the directory /usr/xtmp/. Any files in this directory that have not been accessed in thirty days are purged automatically; please make sure to move any desired files to somewhere more permanent before they expire.
If you need space for a research project, please contact the principal investigators of the project about the possibility of acquiring project space; there might be a project disk available for this purpose.
A more complete description of disk space options can be found in the Computer Science Lab Disk Usage Policy.
Information about managing your disk quota can be found in the document Understanding and Monitoring Your Disk Quota.
Restoring files
To have lost files restored from tape backups, please request that the file be restored by sending your request to the Lab Staff request queue.
As of March 2004, all user and many project filesystems have been moved to a Network Appliance storage appliance. This device provides a snapshot feature which in most cases should allow users to recover lost and deleted files on their own. The snapshots on the file systems will allow you to restore files that were changed or deleted for several hours, days, or even a week ago. To learn more about this feature, please take a look at the Snapshot FAQ.
Personal Computers in CS
Users are permitted to bring in their own computers, and request access to a special-purpose network within the department. Requests to have a computer connected should be made to the Lab Staff and should include your room number and the number of the port you would like to use. The ports are designated by a letter-digit combination, such as B11 or C3. Users should never disconnect department computers from the network, unless so directed by the Lab Staff!
Wireless Network Access
Wireless access within the department is now provided by Duke OIT. For information on managing personal wireless access, or about visitor-access to wireless, please see their wireless access page.
E-mail security issues
Users may occasionally receive e-mails of a suspicious nature, either asking the user for account information (such as passwords) or containing attachments which the user is instructed to open. These e-mails are invariably bogus and the user should ignore these requests. The CS Lab staff will never ask you to provide your password in an e-mail. Additional information about requests for account information (generally referred to as phishing) and suspicious attachments which may contain viruses is available. Users may attempt to alleviate such e-mails, as well as unsolicited SPAM by taking measures to prevent their e-mail addresses from being harvested from department or other web sites.
Mailing Lists
Duke OIT provides campus users with the Sympa mailing list manager: a full-featured e-mail list manager with a web interface. Addresses for these lists have the form list-name@duke.edu.
Please contact the Lab Staff if you require a mailing list to be set up.
Remote access
Users are required to provide for their own ISP's. Duke OIT does provide a list of options available to students, staff and faculty members on their remote access page.
You CS account can be accessed a number of ways from off-site. Information on web access to e-mail and shell access via a standard web-browser can be found in the Web-based Remote Access FAQ. Terminal access is also available via ssh clients.
For general-purpose remote access (as opposed to intensive research computing) we recommend using the login servers (login.cs.duke.edu). Individual desktop machines are not guaranteed to be available, and storing files on these can result in data loss. Please see the Disk Usage FAQ for more information.
General Linux/Unix questions
The Unix/Linux specific questions previously located in this FAQ have been moved to CSL: General in the Linux/Unix tab (final tab) of the tabbed section following the bulleted list at the top.