Computing Facilities    links to the SCS and CMU home pages Carnegie Mellon School of Computer Science Carnegie Mellon University
 
Advanced search tips 
 Documentation
 » Introduction to Facilities 
 » Accounts & passwords 
 » AFS 
 » Application software 
 » AV help 
 » Backups & restores 
 » Calendaring 
 » E-mail 
 » Networking 
 » Printing 
 » Purchasing 
 » Resource management 
 » Security 
 » Software licensing 
 » Support charges 
 » Web publishing 
 » Your health 
 » Mac support 
 » Linux support 
 » Windows PC support 

Corvid — cmuScsDiscardSpam Attribute

Also Known As

Implemented internally in LDAP as the cmuScsDiscardSpam attribute, this feature is also known as:
  • DiscardSpam Flag
  • Discard Spam Flag
  • Spam Flag
  • CMU SCS Discard Spam Attribute

Description

The cmuScsDiscardSpam flag specifies how the SCS Corvid mail system should handle email that Sophos has tagged as spam. The attribute is account-specific and can take one of three values:
  • TRUE - Email tagged as spam will not be delivered
  • FALSE - Email delivery of spam is destination-dependent
  • Not Set - Email delivery of spam is destination-dependent

The current default value is Not Set or blank. When this flag is Not Set or FALSE, the Email Forwarding Address determines behavior.

  • If forwarding is set to a local cmu.edu email address, spam will be delivered
  • If forwarding is set to an offsite, non-CMU email address, spam will not be delivered

Some remote email providers, when they see spam arriving from our servers to a mailbox on their system, may automatically blacklist all email from SCS. Such blanket rejection would affect not only your own legitimate, nonspam email, but also that from other local users who also forward their email to the same provider.

Example

Harry Bovik's cmuScsDiscardSpam attribute has a value of Not Set, meaning that spam-handling depends upon his account's mail-forwarding address. Because Harry has his mailRoutingAddress attribute set to bovik+@imap.srv.cs.cmu.edu, all his incoming mail will be delivered, including messages tagged as spam. While Harry may decide to file such spam automatically into a local SPAM folder, via a client filter, but that process is independent of his cmuScsDiscardSpam configuration.

Limitations

The cmuScsDiscardSpam field is not required, and if an account has no value set, Corvid will attempt reasonable behavior according to the following algorithm. If Sophos has tagged a message as spam, that email can still be delivered to one or more recipients during the email protocol exchange:
  • If all potential recipients are configured to discard spam, either explicitly, by having a value of TRUE or implicitly by having their email forwarded offsite
  • Then the email is rejected
If, however,
  • Some recipients want the spam delivered, and some do not
  • Then the message is accepted from the remote server, and
  • The spam email is delivered to those that want the spam, and
  • The spam email is silently dropped for those that do not want it
The remote sender may or may not see a report of rejection, depending upon:
  • Whether the email was tagged as spam, and
  • To whom the remote sender addressed the message, and
  • The cmuScsDiscardSpam settings of those accounts

How To Change

You can view or modify the value of this attribute via the SCS Corvid lookup page. Contact the SCS HelpDesk, <help+@cs.cmu.edu> or x8-4231, with any questions or problems.