Log in to the SYSTEM account
and enter the following commands interactively (or include them in
the SYS$MANAGER:SYSTARTUP_VMS.COM command procedure before you boot
the system). These commands load the asynchronous driver NODRIVER
(NOA0) and install DYNSWITCH software on your
system.
$ RUN SYS$SYSTEM:SYSGEN
SYSGEN>CONNECT NOA0/NOADAPTER
SYSGEN>EXIT
$ INSTALL:=$SYS$SYSTEM:INSTALL
$ INSTALL/COMMAND
INSTALL>CREATE SYS$LIBRARY:DYNSWITCH/SHARE -
_ /PROTECT/HEADER/OPEN
INSTALL>EXIT
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The system manager of the remote OpenVMS node
must also enter these commands.
Additionally, the system manager at the remote
OpenVMS node must enter the commands given below. These commands enable
the use of virtual terminals for the terminal line that is to be switched,
and set the DISCONNECT characteristic for the terminal line. (The
virtual terminal capability permits the process to continue running
if the physical terminal you are using becomes disconnected.)
$ RUN SYS$SYSTEM:SYSGEN
SYSGEN>CONNECT VTA0/NOADAPTER/DRIVER=TTDRIVER
SYSGEN>EXIT
$ SET TERMINAL/EIGHT_BIT/PERMANENT/MODEM/DIALUP -
_$ /DISCONNECT device-name:
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Device-name is
the name of the terminal port to which the dynamic asynchronous connection
is made.
Establish the required
transmit password at the originating end of the dynamic asynchronous
dialup link. The transmit password is the password sent to the remote
node during connection startup. Use NCP to enter a command to define
the transmit password for the remote node. The password
can contain one to eight alphanumeric characters and should not contain
any spaces. Specify the following commands:
$ RUN SYS$SYSTEM:NCP
NCP>DEFINE NODE node-id TRANSMIT PASSWORD password
NCP>EXIT
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Node-id is the
name of the remote node with which your node is forming a connection.
In the following example, the node name of your
local node is LOCALA, the transmit password is PASSA, and the remote
node with which you are creating a dynamic asynchronous dialup link
is REMOTC:
$ RUN SYS$SYSTEM:NCP
NCP>DEFINE NODE REMOTC TRANSMIT PASSWORD PASSA
NCP>EXIT
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For each remote node with which you will create
a dynamic asynchronous DECnet dialup link, you must define a transmit
password in a separate command.
The system manager for the node at the other end
of the connection must define that same password as a receive password
for your node (the password expected to be received from your node).
The remote system manager should also specify the parameter INBOUND ROUTER or INBOUND ENDNODE,
to indicate the type of node (router or end node) that is expected
to initiate the dynamic connection. These are the commands the
remote manager should enter:
$ RUN SYS$SYSTEM:NCP
NCP>DEFINE NODE node-id -
_ RECEIVE PASSWORD password INBOUND node-type
NCP>EXIT
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For example, if your node LOCALA is an end node
and your transmit password is PASSA, the manager at REMOTC should
issue the following command:
$ RUN SYS$SYSTEM:NCP
NCP>DEFINE NODE LOCALA RECEIVE PASSWORD PASSA INBOUND ENDNODE
NCP>EXIT
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Ensure that DECnet is
running on both nodes for the remaining steps. If you have not already
done so, turn on the network by entering the following command (and
request that the remote system manager also do so):
If the network was already running before you
began the dynamic asynchronous connection procedure, enter these commands
to cause the permanent database entry to be entered in the volatile
database:
$ RUN SYS$SYSTEM:NCP
NCP>SET NODE node-id ALL
NCP>EXIT
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The remaining steps can
be performed by any OpenVMS user with NETMBX privilege. Log in to
your local OpenVMS system, and enter the following DCL command on
your terminal to cause your process to function as a terminal
emulator (which makes the remote terminal appear to be
a local terminal connection):
SET HOST/DTE device-name:
Device-name is
the name of your local terminal port that is connected to the modem.
If both systems use modems with autodial capabilities, you can optionally include
the /DIAL qualifier on the SET HOST/DTE command to cause automatic dialing of the modem on the remote
node, as follows:
SET HOST/DTE/DIAL=number device-name:
If you are not using automatic
dialing, dial in to the remote node manually.
Once the dialup connection
is made and you receive the remote OpenVMS system welcome message,
log in to your account on the remote node.
While logged in to your
account on the remote node, enter the following command to cause the line
to be switched to a DECnet line automatically:
$ SET TERMINAL/PROTOCOL=DDCMP/SWITCH=DECNET
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The following message indicates that the DECnet
link is being established:
%REM-S-END - control returned to local-nodename::
$
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To check whether the communications link has come
up, specify the following command on the local system:
$ RUN SYS$SYSTEM:NCP
NCP>SHOW KNOWN CIRCUITS
NCP>
EXIT
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The resulting display should list a circuit identified
by the mnemonic TT or TX, depending on the asynchronous device installed
on the line, and indicate that it is in the ON state.
When the DCL prompt appears on your terminal screen,
you can begin to communicate with the remote node over the asynchronous
DECnet connection.
As an alternative to switching
the terminal line to a DECnet line automatically (as described in
previous step 7), you can switch the line manually. If you originate
a dynamic connection to an OpenVMS node from a node that is not running
OpenVMS software, manual switching is required; from an OpenVMS system,
it is optional. If you are originating the connection
from a node that is not running OpenVMS software, follow system-specific
procedures to log in to the remote OpenVMS node by means of terminal
emulation.
Once you are logged in to the
remote node, two steps are required to perform manual switching:
Using your account on
the remote OpenVMS node, specify the SET TERMINAL command described
in step 7, but add the /MANUAL qualifier:
$ SET TERMINAL/PROTOCOL=DDCMP/SWITCH=DECNET/MANUAL
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You receive the following message from the remote
node indicating the remote system is switching its line to DECnet
use:
%SET-I-SWINPRG The line you are currently logged over is becoming
a DECnet line
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You should exit from the
terminal emulator and switch your line manually to a DECnet line.
The procedure depends on the specific operating system on which you
are logged in.
The following example shows
how an OpenVMS user originating a dynamic connection would perform
this procedure:
Exit from the terminal
emulator by pressing the backslash (\ ) key and the Ctrl key simultaneously
on your OpenVMS system.
Enter the following command
to switch your terminal line to a DECnet line manually:
$ SET TERMINAL/PROTOCOL=DDCMP TTA0:
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TTA0 is the name of the terminal port on the local
node.
Enter NCP commands to
turn on the line and circuit connected to your terminal port TTA0
manually, as in the following example:
$ RUN SYS$SYSTEM:NCP
NCP>SET LINE TT-0-0 RECEIVE BUFFERS 4 -
_ LINE SPEED 2400 STATE ON
NCP>EXIT
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Asynchronous DECnet is then started on the local
OpenVMS node.
You can terminate the
dynamic asynchronous link in one of two ways:
Break the telephone connection.
Run NCP and turn off either
the asynchronous line or circuit. The two commands you can use are
as follows:
$ RUN SYS$SYSTEM:NCP
NCP>SET LINE dev-c-u STATE OFF
NCP>SET CIRCUIT dev-c-u STATE OFF
NCP>EXIT
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If either of the above NCP commands is entered
at the remote node, the line returns to terminal mode immediately.
If the command is entered at the local (originating) OpenVMS node,
the remote line and circuit remain on for approximately four minutes
and then the line returns to terminal mode.