How to manage ecn.purdue.edu mail aliases

ECN mail servers are configured to take all accounts and provide them with a mail address. If a user or entity has at least one account on an ECN supported Linux host, then that user or entity will get an ECN address. The mail address will be in the form of “username@ecn.purdue.edu“. The user or entity may or may not have a mailbox on one of the ECN mail servers. The mail address is a courtesy so that if mail is addressed as “username@ecn.purdue.edu”, then the ECN mail servers forward their e-mail to their actual mailbox. 

The ECN mail servers maintain a list of mail addresses by using a managed database, stored centrally and periodically updated to reflect changes to the user's or entity's preferred mailbox. The data source for determining the users and entity preferred mailbox was gathered nightly from ACmaint, selecting the mailbox lists in the ACmaint user record «mailHost».

However, in May 2024, the preferred mailbox will no longer be stored in ACmaint. Instead, the location of a user's or entities preferred mailbox will begin with the assumption that all mail addresses will be set to the default, “username@purdue.edu", and only a explicit set of users and entities will receive mail on an ECN mail server. No mechanism will exist for a user to override their mail address, and a support ticket will be needed to change a mailbox.

In the following section is a description of the configuration files that will control mail delivery.

Mail configuration files

All files listed are part of the Linux configuration manager. Each file is managed by the revision control system. Each file is read sequentially, meaning if one file declares a mail address and preferred destination, then subsequent files could override the same mail address with a new destination.

The master file - /usr/share/adm/config/dynamic/aliases.txt

The configuration starts with the master file. This file is automatically generated and contains all users and entities that have at least one Linux account. The default destination is in the form “username@purdue.edu". It is not recommended that this file be changed as any changes will be wiped out on the next automatic nightly update.

The “no mail” file - /usr/share/adm/config/os/common/aliases-nomail.txt

The next file read in the override chain is the “no mail” configuration. Each record in this file will remove a mailbox from the final configuration. This is helpful for users or entities that don't expect mail service. The original data includes those ACmaint «mailHost» records that had a setting of «reject.cc.purdue.edu», «picket.ics.purdue.edu», or «accounts.itap.purdue.edu».

The “ecn” file - /usr/share/adm/config/os/common/aliases-ecn.txt

The next and most important file is the list of users and entities that desire to use an ECN mail server as their mailbox. This file must include the server that will host the mailbox. Only hosts that the configuration manager has marked the host as a mail spooler, the definition «MAILSPOOL», should be used to declare a mailbox.

The “override” file - /usr/share/adm/config/os/common/aliases-override.txt

Next is the file containing users that want to override their mailbox location from the default mailbox. The phrase “double-dippers” has been used to describe the desire to have their mailbox be on the central mail server, but forwards some or all of their mail to their ECN account. The format is the same as the “ecn” file.

The “aliases.local” file - /usr/share/adm/config/os/common/aliases.local

Finally, the local mail aliases file is read. Addresses in this file can include alternative names for established mailboxes, or can refer to multiple addresses when needing a way of addressing mail to a group. 

Updating a mailbox

The procedure for updating a mailbox starts by editing one of the configuration manager's alias files, using the normal “rcsedit” command. Then push the new configuration to the each of the mail servers using the “update-mbox" command. The “update-mbox” command will distribute the new alias files to each of the mail servers and rebuilds the server's alias database. If you're not familiar with making changes or if you have any questions, send a service request ticket to the Linux group and they will make the changes for you. The update takes only a few minutes to complete.