System information

Troubleshooting AppleTalk
Book Title
9-194
AppleTalk: Network Services Intermittently Unavailable
Symptom: Network services are intermittently unavailable. Services come and go without warning.
Table 9-6 outlines the problems that might cause this symptom and describes solutions to those
problems.
Table 9-6 AppleTalk: Network Services Intermittently Unavailable
Possible Problems Solution
Misconfigured access lists
Step 1 Use the show appletalk access-list exec command on routers in the path
from source to destination.
Step 2 Disable any access lists (or just those on a particularly suspect router)
using the no appletalk access-group interface configuration command.
Step 3 After disabling access lists, check whether devices appear in the Chooser.
Step 4 If devices now appear in the Chooser, a misconfigured access list is
probably filtering NBP traffic. To isolate the problem access list, enable
lists one at a time until devices no longer appear.
Step 5 Check the access lists and associated configuration commands for errors.
Configure explicit permit statements for traffic that you want to pass
through the router normally.
Step 6 If problems persist, there might be more than one misconfigured access
list. Continue enabling access lists one at a time and fixing misconfigured
access lists until the problem is solved.
For detailed information about filtering NBP traffic using access lists, refer to the
Cisco IOS Network Protocols Configuration Guide, Part 1.
Possible Problems Solution
Duplicate network
numbers or overlapping
cable-range
In AppleTalk, network numbers must be unique within an internetwork. If duplicate
network numbers exist, packets might not be routed to their intended destinations.
If AppleTalk services do not appear in the Chooser for particular networks, those
networks probably have duplicate network numbers.
Step 1 Change the network number or cable-range of the suspect network to a unique
value using the appletalk cable-range interface configuration command.
Step 2 Use the show appletalk route privileged exec command to view the routing
table. If the network number or cable-range continues to appear in routing
tables, you have found the duplicate (because the other network using that
number will continue to send routing updates).
If the network number or cable-range disappears from the internetwork after
40 seconds, you have not found the duplicate. Change the network number or
cable-range specification back to its previous value and try again to isolate the
duplicate network number.
Step 3 If you changed the network number or cable-range on the interface, remember
to reenter the zone name and any other interface configurations for AppleTalk
on that interface.