System information

Troubleshooting DECnet
Book Title
11-260
DECnet: End Nodes Cannot Find Designated Router
Symptom: End nodes cannot find a designated router. End nodes cannot access nodes that are on
different LANs, but other nodes connected to the same LAN are accessible.
Table 11-3 outlines the problems that might cause this symptom and describes solutions to those
problems.
Table 11-3 DECnet: End Nodes Cannot Find Designated Router
Node address out
of range
Step 1 Use the show running-config privileged exec command to view router
configurations. Check to see whether the decnet max-address global
configuration command has been configured. This command sets the highest
DECnet node number allowed in the area.
Note: The decnet max-address command specifies the highest node number
allowed in an area, not the maximum number of node addresses allowed in an
area. For example, if you configure the command decnet max-address 1000 on a
router and you configure a node with a node address of 1001, the address is out of
range.
Step 2 The default maximum address is 1023. However, if another value is configured,
the node address might be more than the configured value. If this is the case,
increase the maximum address value using the decnet max-address command.
Partitioned area Make sure the network topology has no discontiguous areas. If any discontiguous areas
exist, reconfigure the topology by changing area addresses or by creating a path (with a
router) to create a contiguous network.
Media problem For information on troubleshooting serial lines, refer to Chapter 15, “Troubleshooting
Serial Line Problems.” For information on troubleshooting LAN media, refer to the media
troubleshooting chapter that covers the media type used in your network.
Possible Problem Solution
DECnet not enabled on
router
Step 1 Use the show running-config privileged exec command to view the router
configuration. Determine whether DECnet global configuration and interface
command specifications are configured on the router.
Step 2 Enable DECnet routing on the appropriate routers and interfaces. For detailed
information on configuring DECnet, refer to the Cisco IOS Network Protocols
Configuration Guide, Part 2.
End nodes and router area
number mismatch
Step 1 Check the configuration of end nodes and routers on the network segment.
Check the area address specified on end nodes and routers. Use the show
running-config privileged exec command to view the router configuration.
Step 2 If an end node is not in the same area as a router on the segment, you must
either change the address of the end node to be the same as that of a router on
the segment, or you must reconfigure a router on the segment with the same
area number as the end node.
Possible Problem Solution