Technical Notes for Novell NetWare

The Connection Watchdog

If a workstation terminates PRO/5 abnormally (i.e., if the system crashes or Ctrl-Alt-Del is pressed), NetWare cannot know of this right away, and thus files may not be closed and locks may not be released.

There are two ways that NetWare can discover that a workstation has abnormally terminated:

  • The workstation logs in again.

  • NetWare's connection watchdog logs it out.

The connection watchdog is a safety mechanism built into NetWare so that workstations which cannot be reached for a long period of time may be automatically disconnected, their files closed, and their connection recycled. The NetWare administrator can change the watchdog parameters to adapt its behavior for local needs. If the watchdog is set to function very aggressively, connections can be lost too quickly: for example, if a cable is disconnected briefly while a new node is attached. If the watchdog parameters are too "tame", NetWare could be too slow to determine that a connection was lost and that the corresponding files may be closed.

NetWare watchdog parameters can be entered at the server console or entered in the server's AUTOEXEC.NCF file. BASIS uses the following settings:

SET CONSOLE DISPLAY WATCHDOG LOGOUTS = ON
SET DELAY BEFORE FIRST WATCHDOG PACKET = 30
SET NUMBER OF WATCHDOG PACKETS = 5
SET DELAY BETWEEN WATCHDOG PACKETS = 10

The first setting above causes the console to beep and display a message whenever a watchdog logout occurs. With the watchdog parameters set as above, the NetWare server will probe each workstation for a response after 30 seconds of inactivity. If the workstation does not respond after 5 tries spaced 10 seconds apart, the connection is automatically logged out.

The watchdog is always active, whether or not you change the parameters. However, reports are not issued to the console unless CONSOLE DISPLAY WATCHDOG LOGOUTS is set to ON. With the default watchdog parameters, an inactive connection could remain undetected for approximately 15 minutes.

Adding Another PRO/5

If you have more than one license for the same BASIS product installed on the same network, you should consolidate all users into a single serial number. This will prevent erroneous !ERROR=0 reports.

This is not required when using different BASIS products on the same network based on different operating systems.