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Oracle Solaris Administration: Network Services     Oracle Solaris 11 Information Library
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Document Information


Part I Network Services Topics

1.  Network Service (Overview)

2.  Managing Web Cache Servers

3.  Time-Related Services

Part II Accessing Network File Systems Topics

4.  Managing Network File Systems (Overview)

5.  Network File System Administration (Tasks)

6.  Accessing Network File Systems (Reference)

Part III SLP Topics

7.  SLP (Overview)

8.  Planning and Enabling SLP (Tasks)

9.  Administering SLP (Tasks)

10.  Incorporating Legacy Services

11.  SLP (Reference)

Part IV Mail Services Topics

12.  Mail Services (Overview)

13.  Mail Services (Tasks)

Task Map for Mail Services

Planning Your Mail System

Local Mail Only

Local Mail and a Remote Connection

Setting Up Mail Services (Task Map)

Setting Up Mail Services

How to Set Up a Mail Server

How to Set Up a Mail Client

How to Set Up a Mail Host

How to Set Up a Mail Gateway

How to Use DNS With sendmail

Changing the sendmail Configuration (Task Map)

Changing the sendmail Configuration

How to Build a New File

Setting Up a Virtual Host

How to Automatically Rebuild a Configuration File

How to Use sendmail in the Open Mode

How to Set SMTP to Use TLS

How to Manage Mail Delivery by Using an Alternate Configuration of

Administering Mail Alias Files (Task Map)

Administering Mail Alias Files

How to Set Up an NIS mail.aliases Map

How to Set Up a Local Mail Alias File

How to Create a Keyed Map File

Managing the postmaster Alias

How to Create a postmaster Alias in Each Local /etc/mail/aliases File

How to Create a Separate Mailbox for postmaster

How to Add the postmaster Mailbox to the Aliases in the /etc/mail/aliases File

Administering the Queue Directories (Task Map)

Administering the Queue Directories

How to Display the Contents of the Mail Queue, /var/spool/mqueue

How to Force Mail Queue Processing in the Mail Queue, /var/spool/mqueue

How to Run a Subset of the Mail Queue, /var/spool/mqueue

How to Move the Mail Queue, /var/spool/mqueue

How to Run the Old Mail Queue, /var/spool/omqueue

Administering .forward Files (Task Map)

Administering .forward Files

How to Disable .forward Files

How to Change the .forward-File Search Path

How to Create and Populate /etc/shells

Troubleshooting Procedures and Tips for Mail Services (Task Map)

Troubleshooting Procedures and Tips for Mail Services

How to Test the Mail Configuration

How to Check Mail Aliases

How to Test the sendmail Rule Sets

How to Verify Connections to Other Systems

Logging Error Messages

Other Sources for Mail Diagnostic Information

Resolving Error Messages

14.  Mail Services (Reference)

Part V Serial Networking Topics

15.  Solaris PPP 4.0 (Overview)

16.  Planning for the PPP Link (Tasks)

17.  Setting Up a Dial-up PPP Link (Tasks)

18.  Setting Up a Leased-Line PPP Link (Tasks)

19.  Setting Up PPP Authentication (Tasks)

20.  Setting Up a PPPoE Tunnel (Tasks)

21.  Fixing Common PPP Problems (Tasks)

22.  Solaris PPP 4.0 (Reference)

23.  Migrating From Asynchronous Solaris PPP to Solaris PPP 4.0 (Tasks)

24.  UUCP (Overview)

25.  Administering UUCP (Tasks)

26.  UUCP (Reference)

Part VI Working With Remote Systems Topics

27.  Working With Remote Systems (Overview)

28.  Administering the FTP Server (Tasks)

29.  Accessing Remote Systems (Tasks)

Part VII Monitoring Network Services Topics

30.  Monitoring Network Performance (Tasks)



Resolving Error Messages

This section describes how you can resolve some sendmail–related error messages. You can also refer to

The following error messages contain two or more of the following types of information.

451 timeout waiting for input during source

Cause: When sendmail reads from any source that might time out, such as an SMTP connection, the program sets a timer to the value of various Timeout options before reading begins. If the read is not completed before the timer expires, this message appears and reading stops. Usually, this situation occurs during RCPT. The mail message is then queued for later delivery.

Solution: If you see this message often, increase the value of various Timeout options in the /etc/mail/ file. If the timer is already set to a large number, look for hardware problems, such as poor network cabling or connections.

550 hostname... Host unknown

Cause: This sendmail message indicates that the destination host machine, which is specified by the portion of the address after the at sign (@), was not found during domain name system (DNS) lookup.

Solution: Use the nslookup command to verify that the destination host exists in that domain or other domains, perhaps with a slightly different spelling. Otherwise, contact the intended recipient and ask for a proper address.

550 username... User unknown

Cause: This sendmail message indicates that the intended recipient, who is specified by the portion of the address before the at sign (@), could not be located on the destination host machine.

Solution: Check the email address and try again, perhaps with a slightly different spelling. If this remedy does not work, contact the intended recipient and ask for a proper address.

554 hostname... Local configuration error

Cause: This sendmail message usually indicates that the local host is trying to send mail to itself.

Solution: Check the value of the $j macro in the /etc/mail/ file to ensure that this value is a fully qualified domain name.

Description: When the sending system provides its host name to the receiving system in the SMTP HELO command, the receiving system compares its name to the sender's name. If these names are the same, the receiving system issues this error message and closes the connection. The name that is provided in the HELO command is the value of the $j macro.

For additional information, refer to

config error: mail loops back to myself.

Cause: This error message occurs if you set up an MX record and make host bar the mail exchanger for domain foo. However, you fail to configure host bar to know that it is the mail exchanger for domain foo.

Also, another possibility is that both the sending system and the receiving system are identifying as the same domain.

Solution: For instructions, refer to

host name configuration error

Description: This is an old sendmail message, which replaced I refuse to talk to myself and is now replaced by the Local configuration error message.

Solution: Follow the instructions that were provided for resolving this error message, 554 hostname... Local configuration error.

user unknown

Cause: When you try to send mail to a user, the error Username... user unknown is displayed. The user is on the same system.

Solution: Check for a typographical error in the entered email address. Otherwise, the user could be aliased to a nonexistent email address in /etc/mail/aliases or in the user's .mailrc file. Also, check for uppercase characters in the user name. Preferably, email addresses should not be case sensitive.

For additional information, refer to