You may experience the following commonly occurring problems with serial ports on a UNIX platform:

Rhapsody Fails to Open the Port

If Rhapsody fails to open the serial port, then verify that Rhapsody has access to the port:

  1. Check ownership on /dev/ttyS* (the device you are trying to open) by executing ls -l /dev/ttyS*and ensure Rhapsody has the appropriate permissions, for example:

    crw-rw---- 1 root dialout 4, 64 2012-01-04 1164 2012-01-04 11 :56 /dev/ttyS0
crw-rw---- 1 root dialout 4, 65 2012-01-04 11:56 /dev/ttyS1
crw-rw---- 1 root dialout 4, 66 2012-01-04 11:56 /dev/ttyS2
crw-rw---- 1 root dialout 4, 67 2012-01-04 11:56 /dev/ttyS3
crw-rw---- 1 root dialout 4, 68 2012-01-04 11:56 /dev/ttyS4
crw-rw---- 1 root dialout 4, 69 2012-01-04 11:56 /dev/ttyS5
crw-rw---- 1 root dialout 4, 70 2012-01-04 11:56 /dev/ttyS6
crw-rw---- 1 root dialout 4, 71 2012-01-04 11:56 /dev/ttyS7
crw-rw---- 1 root dialout 4, 72 2012-01-04 11:56 /dev/ttyS8
crw-rw---- 1 root dialout 4, 73 2012-01-04 11:56 /dev/ttyS9
  2. If not, issue the following command as a root user: chmod 666 /dev/ttyS*.
  3. If the problem persists, please consult the relevant Unix documentation or contact Rhapsody Support.

Rhapsody Keeps Warning About Lock Files

When Rhapsody is unable to create or access a lock file, it issues a warning. To address the problem, Rhapsody must be granted permission to access the lock directory or pre-existing lock file on the system.

The following solution is recommended:

  1. Ensure that Rhapsody can access the serial port.

  2. Ensure that the Rhapsody user is a member of the group which owns those ports. If necessary add the Rhapsody user to the appropriate group in /etc/group (for example, issue the command edit /etc/group and add the name of the user that runs the Rhapsody process to the end of the uucpgroup line (daemon for HPUX)).

    On the Redhat 5.5 platform, the user must be added to both the uucp and lock groups.

  3. Ensure that that group has write permissions for /dev/ttyS*.
  4. Check the ownership of the uucp lock directory - typically /var/spool/locks. On some platforms you may also need to change the permissions on this directory by executing the following command as a root user: chmod 775 /var/spool/locks.
  5. Ensure that the Rhapsody user is a member of the appropriate group, and that group has write permissions for the lock directory.