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Summary

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Although the resource becoming unavailable or a down network can

cause this problem, it is also possible for the cause to be an access list or
workstation problem.

To troubleshoot an access list issue or other restriction, the administrator

should use the show appletalk access-list command to review any
filters and the no appletalk access-group command to disable the list for
testing. After locating the offending access list, the administrator will likely
wish to reconfigure the list with appropriate permit and deny statements, as
warranted by security policies.

However, it is also possible that the problem is isolated to the worksta-

tion. Ideally, help desk staff will have performed a preliminary assessment of
the problem, which should include asking the caller if other users are
currently experiencing the problem. If the problem does not affect other
users, it is possible that the workstation itself has a disconnected cable or
that the internal network configuration has changed. Macintosh systems can
use a network card for their network connections or the serial port, with the
default being a serial port connection. This should be checked by using
the AppleTalk control panel.

A specific type of access list is available to limit zone information.

Applied to individual interfaces, the administrator may use the appletalk
getzonelist-filter 610

command. This command would apply access

list 610 to any zone updates composed by the router. Such an access list
would be a likely candidate for missing resources in the Chooser.

Summary

his chapter addressed troubleshooting connectivity issues in AppleTalk

networks. It reviewed the AppleTalk addressing scheme, including phase one
and phase two network addresses. In addition, the chapter covered AppleTalk
zones, overlapping cable ranges, NBP issues, and RTMP limitations.

It is hoped that administrators reading this chapter have also noted

the importance of good documentation, large cable range definitions
for scalability, and the use of descriptive zone names to assist in user
acceptance and troubleshooting.

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