Upgrading your system to UnixWare 7

Upgrading Mail and Messaging

SCO OpenServer 5, SCO UnixWare 2.X and UnixWare 7 all contain different mail transport systems with different methods of configuration. However, the feature sets are similar and most features do migrate easily. This topic discusses those features that feature prominently in the GUI or character based configuration tools. (The mail transport in UnixWare 7 is modelled after the SCO OpenServer one, which makes duplicating complex configuration a little easier from that direction.)

Mail folder formats are completely backwards-compatible from UnixWare 7 to both of the other systems, and so folders can be imported with ease.

The following major areas are addressed by this document:

users' inboxes
Mail and Messaging transport configuration
aliases
vacation notifications
customized forwarding options
virtual domains

Each of these is described according to whether the migration path is to UnixWare 7 from SCO OpenServer or from SCO UnixWare Release 2.X. In both cases, the text assumes that you are starting with a default configuration on UnixWare 7 and attempting to modify it to match your previous configuration.

Note that this topic describes how to preserve the simple configuration options that were provided in the configuration programs (SCO UnixWare Release 2.X provided a GUI-based configuration tool for mailsurr, while SCO OpenServer provided a GUI for MMDF and a command line script for sendmail).

Upgrading SCO UnixWare Release 2.X Mail and Messaging

This topic describes the migration path from SCO UnixWare Release 2.X to UnixWare 7 for various aspects of the Mail and Messaging system.

Preserving users' inboxes

User's inboxes in SCO UnixWare Release 2.X are in /var/mail, and remain there for UnixWare 7. It is therefore sufficient to copy these files to the new machine. No data conversion of these files is required.

NOTE: In the case where mailboxes are in users' home directories, these must be restored and the INBOX location configured to point there.

Using the Mail Manager to change the inbox location to users' home directories, change the ``Users' INBOX Location'' setting (within the ``Folder Configuration'' container) to the appropriate setting.

Preserving transport agent configuration

The SCO UnixWare Release 2.X UNIX Mail Setup configuration manager specifies several items. This topic explains how to duplicate similar behavior on UnixWare 7.

In the ``Basic'' configuration category, the following fields are displayed:

Smarter Host
If messages are to be routed to a ``smarter host'', this field contains the identifier of the desired host, and the ``Route All Msgs to Smarter Host?'' prompt is set to No.
This feature can be duplicated in UnixWare 7 using the Settings Bad Host Forwarding/Delay menu option to enable forwarding to the smart host. This has the effect of sending SMTP mail addressed to an unknown host to that specified host.
If the ``Route All Msgs to Smarter Host?'' prompt is set to Yes, then see the description of the ``Route All Msgs to Smarter Host?'' field for how to duplicate the functionality in UnixWare 7.
Cluster Name
This field is analogous to the ``Mail Comes From'' field in the UnixWare 7 ``Basic Configuration'' category except that a blank value is equivalent to setting the ``Mail Comes From'' value to match the host name.
Route All Msgs to Smarter Host?
If this prompt is set to Yes, enable the badhost channel. Additionally, open the ``Mail Delivery Channels'' category in the UnixWare 7 Mail Manager tool, then open the SMTP channel, and change the forwarding host to the ``smarter host'' name. This has the effect of sending all SMTP mail to the smarter host, for both known and unknown hostnames.
Route local messages through MHS?
A direct MHS mail gateway is not supported by UnixWare 7, so there is no analog to this feature.
Log Messages?
UnixWare 7 sendmail has a variety of logging features, some of which are turned on by default. For more information on these, see ``sendmail operations'' in SCOhelp. In general, sendmail logging goes to syslogd, which is the standard logging place.

The ``Advanced'' configuration section of the SCO UnixWare Release 2.X UNIX Mail Setup tool contains several parameters that have no GUI-based analogs in UnixWare 7's sendmail. sendmail does support all of those features, however, a hand edit of /etc/sendmail.cf being necessary to precisely duplicate the SCO UnixWare Release 2.X behavior. The following is a description of what you need to do to duplicate the configuration on UnixWare 7:

The default UnixWare 7 configuration has all of the headers in the SCO UnixWare Release 2.X advanced section enabled. To change this, you must look for a line in /etc/sendmail.cf that starts with the letter ``H'' and references the header line in question. Merely remove (or comment out) the line in question to duplicate an ``off'' button in the SCO UnixWare Release 2.X configuration. In general, precisely duplicating header line generation is not necessary and SCO recommends leaving /etc/sendmail.cf alone in this case.
mailsurr configuration variables do not carry forward to sendmail, so no analog is available.
Debug levels are available in sendmail, but only from the command line and not via a preconfigured value. For more on sendmail debug levels, see ``sendmail operations'' in SCOhelp or the highly recommended O'Reilly book¹ for a truly exhaustive account of sendmail's numerous debugging options.

Footnotes

¹: sendmail, Bryan Costales with Eric Allman, O'Reilly & Associates, Inc.

Preserving vacation notifications

Users of SCO UnixWare Release 2.X will have configured their vacation notifications from dtmail, the graphical mail user agent from CDE. Under UnixWare 7, they should use the Vacation Manager, accessible from the CDE desktop under the Mail panel.

The following SCO UnixWare Release 2.X files must be migrated:

~/.forward
SCO UnixWare Release 2.X users will have their vacation notification enabled by their ~/.forward file. While this file may be brought as-is for use on a UnixWare 7 system, SCO recommends conversion of ~/.forward to ~/.maildelivery, in order to retain compatibility with the UnixWare 7 Vacation Manager. To enable vacation notification, an entry in ~/.forward of the form
```
 
"|/usr/ucb/vacation" 
```
has an equivalent ~/.maildelivery entry of
```
 
*	-	pipe	R	vacation 
```
For a full discussion of ~/.forward and ~/.maildelivery syntax, see the forward(4) and maildelivery(4) manual pages.
~/.vacation.msg
SCO UnixWare Release 2.X users will have to convert their vacation notification message from the file ~/.vacation.msg into two corresponding UnixWare 7 files:
- ~/tripsubject
- ~/tripnote
The body of the message in ~/.vacation.msg should be transferred to ~/tripnote, while the Subject header text should be put into ~/tripsubject.
NOTE: Only the Subject header text, and not the actual Subject: header itself, should be in ~/tripsubject. Also, while other headers may be specified in ~/.vacation.msg, this is not possible in the UnixWare 7 ~/tripnote and ~/tripsubject files.

Preserving aliases

If your SCO UnixWare Release 2.X system uses a mailsurr file for mail configuration (you do not use sendmail as mail transport agent), then the following files must be migrated to your UnixWare 7 system:

/etc/mail/namefiles
On SCO UnixWare Release 2.X systems, all alias files are specified in the file /etc/mail/namefiles. Entries in this file take the form of pathnames to files or directories. If to a directory, then files within this directory are named after the alias, and the file contents specify the actual mail address or addresses. By default, /etc/mail/namefiles specifies the file /etc/mail/names as the aliases file, and the directory path /etc/mail/lists.
Multiple alias files may also be specified for the UnixWare 7 mail system, via the Mail Manager. Any files specified in the SCO UnixWare Release 2.X /etc/mail/namefiles file must be added to the list of alias files displayed in the Mail Manager, which will update the sendmail.cf configuration file appropriately. By default, these files are located in /etc/mail (and the default aliases file on UnixWare 7 is /etc/mail/aliases), but any path may be specified. These files must be converted to a sendmail format aliases file (see the description of /etc/mail/names).
For each entry which is a directory name in /etc/mail/namefiles, the files under that directory must be converted into sendmail style aliases, and then put into an existing or new alias file. For example, suppose /etc/mail/namefiles contains the directory /etc/mail/lists, and the file /etc/mail/lists/engr exists with the following contents:
```
 
fred 
barney 
```
Then the following alias can be created in an alias file:
```
 
engr: fred, barney 
```
/etc/mail/names
The default aliases file on SCO UnixWare Release 2.X systems is /etc/mail/names. This file, and any alias file defined in /etc/mail/namefiles, must be converted to sendmail format for use on UnixWare 7 systems.
Conversion to sendmail alias file format:
- Comments are lines beginning with a hash sign (#) in both formats, and do not need to be altered.
- SCO UnixWare Release 2.X alias entries have white-space separated tokens of the following form:
```
 
name addr1 addr2 addr3 
```
  These must be changed to the form:
```
 
name: addr1, addr2, addr3 
```
  The main difference is the colon separator between alias name and recipient list, and the use of commas to separate addresses. (The white-space is optional in the UnixWare 7 format.)
- In SCO UnixWare Release 2.X alias files, lines may be continued by placing a backslash (\) at the end of the line. In a sendmail format alias file, a continuation line is created by indenting the line with white-space. So for example, an alias such as
```
 
name addr1 addr2 addr3\ 
addr4 
```
  would be converted to
```
 
name: addr1, addr2, addr3, 
  addr4 
```
  Once alias files have been converted and put onto your UnixWare 7, their corresponding databases must be created using the newaliases(1M) utility.

If the BSD Compatibility Package was installed on your SCO UnixWare Release 2.X system, and you are now using sendmail as the mail transport agent, then the following files should be migrated to the UnixWare 7 system:

/etc/ucbmail/aliases
The location of the aliases file is defined by the OA option line in the sendmail configuration file /etc/ucbmail/sendmail.cf. The default location is /etc/ucbmail/aliases. However, you should check the sendmail.cf file. This aliases file may be brought forward to the UnixWare 7 system without modification, and the location specified by the Mail Manager. However, you must ensure that aliases which use redirection to files or pipes have corresponding directory paths or programs which exist. The aliases database file(s) should then be created using the newaliases(1M) utility.
~/.forward
User-defined ~/.forward files may be migrated to UnixWare 7 systems (with the modification discussed in ``Preserving vacation notifications'') to use the vacation notification feature.

Preserving custom forwarding

Users on SCO UnixWare Release 2.X systems had the ability to configure mail forwarding via the /bin/mail program's -F option. On UnixWare 7, /bin/mail is now equivalent to mailx(1), so the -F option is not available. However, similar functionality is supplied by the use of ~/.forward and ~/.maildelivery. The following lists the SCO UnixWare Release 2.X /bin/mail forwarding options, and their equivalent in either ~/.forward or ~/.maildelivery.

mail -F recipient ...
- ~/.forward
  In a ~/.forward file, add each recipient you wish to forward your mail to. Separate recipients with commas if they all appear on the same line, or put a single recipient per line. For example:
```
 
recipient1, recipient2@thishost.com, recipient3 
recipient4 
recipient5 
```
  This causes your mail to be forwarded to five other addresses.
- ~/.maildelivery
  In a ~/.maildelivery file, use the maildelivery(4) pipe (|) action to pipe the message to sendmail for redelivery. For example, to forward your mail to recipient1 and recipient2, create the following line in ~/.maildelivery:
```
 
*   -   |   A   /usr/lib/sendmail recipient1 recipient2 
```
  Note that this does not create any Recent-headers, so the message will appear in the forwarded recipient's mailbox with only the original From and To addresses.
mail -F '|/usr/bin/sh -c "shell_command_line"'
- ~/.forward
  The SCO UnixWare Release 2.X /bin/mail -F option allowed recipients to be commands (called ``Personal Surrogates'') to which the mail message would be piped.
  Similar functionality is available in ~/.forward with the following syntax:
```
 
"|shell_command_line" 
```
  The quotes are necessary if shell_command_line contains white space; that is, if the command has arguments. For example, to set automatic replies for extended absences, you could add the following entry to your ~/.forward file:
```
 
\user, "|/usr/bin/vacation user" 
```
  The recipient ``\user'' tells sendmail to also deliver the message to the user's mailbox, and skip additional alias transformations. This may be used to replace the ``>|'' prefix, which allows SCO UnixWare Release 2.X mail to append the message to the user's mailbox, in addition to executing the pipe command (``Post-processed Personal Surrogates'').
  NOTE: sendmail sorts all addresses in ~/.forward and deletes duplicates before delivering to any of them, therefore ensure that programs in ~/.forward are unique. This can usually be accomplished through the use of the program's command-line arguments.
- ~/.maildelivery
  Piping a message to a program can be accomplished in a ~/.maildelivery entry which uses the pipe (|) action. Using the same example, the equivalent ~/.maildelivery entry would be as follows:
```
 
*   -   |   R   /usr/bin/vacation 
```
  The ``R'' result specified in the fourth column specifies that the message is not to be considered delivered by the action, causing the message to be delivered into the user's mailbox as well. This is the equivalent of the ``>|'' prefix for the SCO UnixWare Release 2.X mail Post-processed Personal Surrogate functionality.
  NOTE: There is no ~/.forward or ~/.maildelivery equivalent of the %c or %S keys used to textually substitute the value of the Content-Type: header, or Subject: header lines in mail -F pipe program recipients. The %R key, which represents the return path to the message sender, may be replaced with the $(sender) variable in ~/.maildelivery. There is no equivalent syntax for ~/.forward.

Those SCO UnixWare Release 2.X systems with the BSD Compatibility Package installed, and which use sendmail as the mail transport agent, will be able to transfer users ~/.forward files to UnixWare 7 systems without modification, as long as those programs, files, and recipients referenced in the ~/.forward files are accessible.

Upgrading SCO OpenServer Release 5 Mail and Messaging

This topic describes the migration path from SCO OpenServer Release 5 to UnixWare 7 for various aspects of the Mail and Messaging system.

Preserving users' inboxes

In SCO OpenServer Release 5, users' inboxes are in /usr/spool/mail, and in /var/mail in UnixWare 7. There is a symbolic link to /usr/spool/mail from /var/mail, and it is therefore sufficient to copy these files to the new machine. No data conversion of these files is required.

NOTE: In the case where mailboxes are in users' home directories, these must be restored and the INBOX location configured to point there.

Using the Mail Manager to change the inbox location to the users' home directories, change the ``Users' INBOX Location'' setting (within the ``Folder Configuration'' category) to the appropriate setting.

Preserving transport agent configuration

SCO OpenServer Release 5 supports two mail transport agents: MMDF and sendmail. Preserving these configurations is described separately:

Preserving SCO OpenServer MMDF configurations.
UnixWare 7 sendmail has been modelled after MMDF to make the transition easier: even advanced features such as the domain table and channel support are supplied. Not all of these are covered in this topic, but after you become familiar with UnixWare 7's sendmail configuration, it should become clear how to port even advanced MMDF configurations to UnixWare 7's sendmail.
The primary screen of SCO OpenServer Release 5's MMDF Configuration Manager allows you to configure the host name, enable SMTP and UUCP, enable domain hiding, and enable or disable the name service methods.
- The entry in the ``Host Name'' field under MMDF should be exactly the same as that given in the ``Host Name'' field in the UnixWare 7 manager's ``Basic Configuration'' category.
- Selecting entries in ``Networks'' amounts to adding channels for each network desired. SMTP is on by default in UnixWare 7, and does not need to be disabled even if no network card is in the machine.
  The UnixWare 7 Mail Manager enables UUCP by selecting the Settings UUCP Enable/Disable menu option.
- ``Format for Mail User Addresses'' in MMDF is analogous to ``Mail comes from'' in the ``Basic configuration'' category of the UnixWare 7 manager. Duplicate the domain setting (the right hand part of the mail address) in the UnixWare 7 configuration.
- ``Name Service Lookup Methods'' are automatic in UnixWare 7, and do not require configuring.
The additional options under ``Forwarding'' in the MMDF Configuration Manager are as follows:
- ``Unknown Hosts Forwarding'' creates a badhost channel in MMDF. The badhost channel in UnixWare 7 functions equivalently and may be enabled by selecting the Settings Bad Host Forwarding/Delay menu option and entering the host name from the MMDF configuration to preserve this functionality. If the MMDF setting is ``Return mail for unknown hosts to sender'', then do nothing (that is, do not create a badhost channel), as this is the default behavior in UnixWare 7.
- ``Unknown User Forwarding'' creates a baduser channel in MMDF. The baduser channel in UnixWare 7 functions equivalently and may be enabled by selecting the Settings Baduser Enable/Disable menu option and entering the host name from the MMDF Configuration Manager to preserve this functionality. If the MMDF setting is ``Return mail for unknown users to sender'', then do nothing (that is, do not create a baduser channel), as this is the default behavior in UnixWare 7.
SCO UnixWare Release 2.X MMDF mailbox locations may be either /usr/spool/mail or the users' home directories. UnixWare 7 implements exactly the same feature, which is accessed via the ``Folder Configuration'' category in the UnixWare 7 mail configuration tool.
The ``Redirection'' option in the MMDF configuration calls up the aliases editor. The same functionality exists in UnixWare 7 and is accessed by opening the ``Alias Files and Maps'' category and selecting the alias file entry. Then select the ``Edit'' facility in the dialog box and the alias editor is started for the system-wide mail alias file.
SCO recommends importing alias files rather than typing in the aliases by hand into the alias editor.
Preserving SCO OpenServer sendmail configurations.
The sendmail configuration is obtained and/or modified by running mkdev cf on SCO OpenServer. It contains several options, each of which is described here. In addition, SCO OpenServer sendmail supports some of MMDF's features, notably configurable INBOX location which is also described here.
- UUCP connections are enabled and disabled in the UnixWare 7 mail manager via the Settings UUCP Enable/Disable option. Manual editing is not allowed in the GUI, as UUCP's Systems file is automatically parsed into the mail configuration. If you wish to have a private map (in other words, you do not have all of the systems in UUCP Systems file used as mail destinations), merely change the name of the UUCP channel's table file and edit it yourself.
- The manual domain entry for mkdev cf is analogous to the ``Mail Comes From'' entry in the ``Basic Configuration'' category of the UnixWare 7 mail configuration utility. You may do domain-hiding (make one machine pretend to be part of a larger entity) if you like.
- NIS support is automatic in UnixWare 7 if NIS is installed and configured.
- Alternate host names may be entered and they function the same on UnixWare 7 with the exception that you do not have to enter the short name of a machine into the alternate name list: instead, the short name is added automatically.
- UnixWare 7 does not have an option to automatically forward UUCP style addresses to the machine uunet.
- UnixWare 7 does have the ability to forward UUCP traffic destined for a host (which must be known to use UUCP) to a UUCP gateway. UUCP has its own configuration file in /etc/uucp/Systems, which keeps a list of all hosts known to UUCP. When a UUCP channel is present, the Mail Manager will automatically update the mail system's internal tables to match the UUCP configuration. Thereafter, any mail addressed to a host in the UUCP table will be forwarded to the UUCP system for delivery.
  This feature is enabled by using the Settings UUCP Enable/Disable menu option to enable the UUCP channel. Then edit the ``Forward all mail to'' entry in the UUCP channel to add the UUCP gateway name.
  Note that, if the UUCP gateway is on the Internet, you would use the same strategy with a custom SMTP channel (that is, leave the DNS one alone, and create a new one for this option). To do this, create a new channel with channel program as SMTP, table type as UUCP Systems file, and the channel name something like uucpgate. Then edit the ``Forward all mail to'' option to point to the UUCP gateway.
- A ``smart host'' is a host to which all mail addresses containing an at-sign (@) are sent. The intent is for machines that do not have access to a name service to forward their mail traffic to a machine that does have such access.
  This feature can be be duplicated on UnixWare 7 by configuring the default SMTP channel to have the ``Forward all mail to'' option pointing at the smart host. Also, add a badhost channel (using the Settings Bad Host Forwarding/Delay option) that also points to the smart host.
  This will cause all known (via the SMTP channel) and unknown (via the badhost channel) hosts to be resolved to the smart host.
- The UnixWare 7 configuration tool does not directly support adding an X.400 gateway product to the system. However, adding a new SMTP channel with a list of hosts to be forwarded to the X.400 gateway is possible.

Preserving virtual domain support

The SCO OpenServer 5.0.4 sendmail supports virtual domains under POP. UnixWare 7 supports virtual domains and adds IMAP support as well.

SCO OpenServer used virtual users (fake users known only to the POP server), whereas UnixWare 7 uses real users and exports them via a user map into the virtual domains.

Refer to ``The Virtual Domain User Manager'' in SCOhelp for details of how to set up virtual domains and export users to those domains. The virtual domain POP users' inboxes on SCO OpenServer are contained in the directory /usr/internet/ip/ip_addr/sco_mail/spool, where ip_addr is the IP address of a virtual domain. The inboxes are named after the virtual user names.

These mailboxes do not need to be reformatted, but do need to be moved into the standard place for inboxes (by default, /var/mail) on UnixWare 7.

In UnixWare 7, virtual users' password information is contained in /var/internet/ip/ip_addr/passwd. This file is in the old style UNIX /etc/passwd format where the encrypted password is contained in the same file as the user ID information. SCO OpenServer normally splits out the encrypted password into /etc/shadow, and places an ``x'' in that field in /etc/passwd.

Preserving vacation notifications

For additional information on the vacation notification features, see ``The Vacation Notification Manager'' in SCOhelp and the vacation(1) and maildelivery(4) manual pages.

Migration from OpenServer MMDF MTA:
The following SCO OpenServer Release 5 files must be migrated:
- ~/.maildelivery
  OpenServer users who have MMDF as their mail transport agent must make the following change in their ~/.maildelivery file:
```
 
*	-	pipe	R	rcvtrip 
```
  becomes
```
 
*	-	pipe	R	vacation 
```
- ~/.alter_egos
  ~/tripnote
  ~/triplog
  If users have any of the above files on SCO OpenServer Release 5, they may be brought as-is onto a UnixWare 7 system. Their functionality is identical to that on OpenServer.
Migration from SCO OpenServer Release 5 sendmail MTA:
OpenServer users who have sendmail as their mail transport agent should convert their ~/.forward and ~/.vacation.msg files as described for migrations from SCO UnixWare Release 2.X.

Preserving aliases

If you are using MMDF as your mail transport agent:
All alias files in SCO OpenServer Release 5 are specified by the ALIAS keyword and table parameter in /usr/mmdf/mmdftailor. For example, the entry
```
 
ALIAS table=aliases 
```
specifies an alias file named aliases. The directory under which the alias files are located is specified in mmdftailor by the MTBLDIR keyword. For example:
```
 
MTBLDIR=/usr/lib/mail/aliasfiles 
```
In this case, the full pathname to the alias file would be /usr/lib/mail/aliasfiles/aliases. By default, if you do not have MTBLDIR defined in the mmdftailor file, the directory is defined to be /usr/mmdf/table.
All alias files may be specified for your sendmail configuration on UnixWare 7 systems by using the Mail Manager. In addition, the files must be converted to sendmail alias file format:
- Comments are lines beginning with a hash sign (#) in both formats, and do not need to be altered.
- Simple aliases of the form
```
 
name: addr1, addr2, addr3 
```
  are used in both formats, and will not need modification.
- Redirection of a message to a file in an SCO OpenServer Release 5 MMDF-style alias uses the following syntax:
```
 
alias:login/file 
```
  For example, ``foobar:dpk/foobar'' would cause user and group IDs to be set to those of the user dpk, and the text of the message to be appended to the file foobar in dpk's default login directory. Similarly, ``foobar:dpk//tmp/foobar'' would do the same for file /tmp/foobar.
  On UnixWare 7, redirection of a message to a file is specified differently. If any addresses to the right of the colon in the alias list begin with a slash (/) character, sendmail interprets the address as the name of a file, and appends the mail message to that file. The filename must be a full pathname, and there is no notion of being able to specify a file relative to a user's default login directory. So, using the previous example, if the home directory of user dpk is known to be /home/dpk, then the alias ``foobar:dpk/foobar'' would be converted as follows:
```
 
foobar: /home/dpk/foobar 
```
  The user and group ID of the file is specified by other sendmail mail delivery agent options. See ``sendmail operations'' in SCOhelp for more information.
- Redirection of a message to a pipe is available for use with MMDF in SCO OpenServer Release 5. The following would cause a message to be passed into a UNIX pipe (see pipe(2)) with user ID and group ID set to those of the user news:
```
 
news-inject:news|/usr/lib/news/uurec 
```
  In UnixWare 7, sendmail format alias files, a program address may take the following forms:
  - |prg
  - "|prg args"
  - |"prg args"
  The prg is the full path of the program to be run. Note that if command-line arguments are needed for the program, they must follow prg, and the entire expression must be quoted (the leading quotation mark may either precede or follow the |).
  So, converting the previous example to sendmail alias file format would yield:
```
 
news-inject:|/usr/lib/news/uurec 
```
  Again, the OpenServer specification of the user ID and group ID by the ``news'' prefix is not allowed for UnixWare 7. sendmail uses other methods for this functionality.
- OpenServer, MMDF-style aliases also allow you to specify the value-part of an entry as a filename, so that the actual value is taken from the file. There are two possible notations for this:
  1. By having left-angle bracket (<) precede the value specification. For example:
```
 
mother: < /etc/mmdf/mother_list@udel-relay.arpa 
```
  2. By using a data type with value ``:include:''. For example:
```
 
mother: :include: /etc/mmdf/mother@udel-relay.arpa 
```
  In both cases, the @HOST is optional.
  On UnixWare 7 systems, sendmail does allow a special notation in the right-hand side of an alias to read its list of recipients from an external file. The format is as follows:
```
 
aliasname: :include:/path 
```
  The expression ``:include:'' must appear exactly as shown, but optional white space is allowed between the ``:include:'' and ``/path''. The ``/path'' is the full pathname of a file containing a list of recipients. However, you may not specify an @HOST as is possible for SCO OpenServer Release 5. See ``sendmail operations'' in SCOhelp for more information concerning ``:include:'' lists.
If you are using sendmail as your MTA:
- /usr/lib/mail/aliases
  The location of the aliases file is defined by the OA option line in the sendmail configuration file /usr/lib/sendmail.cf. The default location is /usr/lib/mail/aliases. However, you should check the sendmail.cf file. This aliases file is compatible with the UnixWare 7 system without modification, and the name and location may be specified by the Mail Manager. However, you must ensure that aliases which use redirection to files or pipes have corresponding directory paths or programs which exist. The aliases database file(s) should then be created using the newaliases(1M) utility.
- ~/.forward
  User-defined ~/.forward files may be brought forward to UnixWare 7 systems (with the modification discussed in ``Preserving vacation notifications'') to use the vacation notification feature.

Preserving custom forwarding

On SCO OpenServer Release 5 systems using MMDF as mail transport agent, users' ~/.maildelivery files are compatible with UnixWare 7, and may be transferred with little modification. However, the following programs popular with use in ~/.maildelivery on OpenServer are not available in UnixWare 7:

/usr/bin/rcvalert
/usr/bin/rcvfile
/usr/bin/rcvprint
/usr/bin/rcvtrip
/usr/bin/resend

Use of /usr/bin/vacation in ~/.maildelivery to replace rcvtrip is discussed in ``Preserving vacation notifications''.

On OpenServer systems that use sendmail as the mail transport agent, users' ~/.forward files are also compatible with UnixWare 7 and may be transferred with little modification. Users must simply ensure that programs, files, and recipients referenced in their ~/.forward files are accessible. See also ``Preserving vacation notifications''.