NIO CommKit Host Interface Installation and System Administration Manual

3-2
Control Tables (from AT&T 255-110-127)
Introduction
Introduction
This chapter describes the control tables that must be edited to reflect your
data switch network environment. These tables are used when a call is
received or sent through the CommKit Host Interface. The CommKit Host
Interface software relies on these tables to implement call validation for such
services as login, remote login, remote execution, and file transfer. The
control tables also specify the information required to process these services.
The CommKit Host Interface tables (residing in /etc/opt/dk) are:
dkdotab used for outgoing calls dkuidtab used for incoming calls
dkhosts used for outgoing calls srvtab used for incoming calls
Overview of Control Tables
When using the dk command, the dkhosts table is scanned for a match of
the host name and service type (l for remote login, x for remote execution)
with the host and classes fields in the dkhosts table. If a match is found, the
Dialstring and Miscellany fields are used to construct the dialstring that is
sent to place the call.
When an incoming call is received, the srvtab table is scanned by the
dkserver program until a match is found on the system, service, and user
fields with the same fields of the incoming dialstring. When a match is
found, the remaining fields in srvtab determine what program is to be exe-
cuted on that channel (such as login, uucp, push, pull, etc.). If a match is
not found, the incoming call is denied access to the host.
The dkdotab table is parsed when the dkdo service is invoked on the local
host, looking for a match on the command field in the dkdotab table with
the command argument to dkdo. When a match is found, the remaining
fields indicate on which host to execute the command, what flags affect the
operation of dkdo, and what files are associated with the command.
Finally, the dkuidtab table is scanned on incoming calls to validate and map
incoming user IDs with valid user IDs on the local system. The dkuidtab
table is scanned if the value of the user field in the srvtab table is an & or if