AT&T 3B2 Maintenance Reference Manual page 247

Feature Cards
Failures in the ports diagnostics are typically caused by the following:
11
defective ports card
11
defective I/O backplane slot
11
defective system board
11
bad diagnostic code
H the only evident problem is the ports card itself,
it
is unlikely that the diagnostic code is bad
or that the system board is defective. If there are two equipped devices, a quick check of
defective slots rather than defective cards is to change locations and see if the fault follows the
slot or the card.
NOTE:
The software entries will be different if the exchange of cards involves a ports and a
network interface (or other) card. This wm be done automatically, but
it
requires two boots to
dear up errors.
Software Problems
Problems with ports cards may be caused by improper loading of software. The relevant files
to check are /dev and /etc/inittab. The /dev entries should look like:
crw--w--w-
1
(owner) (owner)
slot, port Nov 28 15: 46 tty??,
where
owner
is the last owner (uid and gid), slot is the backplane slot, and port is the
connector number on the card (0-4). The?? (in tty??) also refers to the backplane slot and
card connector number
(1-5).
The /etc/inittab entries should look like:
??:2:respawn:/etc/getty tty?? baud #card? port?
where baud will be a number like
9600, 1200,
and so on. Additional sample entries a:re given
in the
AT&T 3B2 Computer Expanded Input/Output Capability Manual
(305-452). If changes are
required, use the sysadm and ttymgmt commands. For those more experienced with the
UNIX system, the proper entries can be made using the standard UNIX commands. See the
AT&T 3B2 Computer System Administrator's Guide
for procedures for creating or changing /dev
and/etc/inittab entries.
110 Feature Cards
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