Hidden Value: DTC connections, PC automated downloads and custom prompts
HiddenValue details commands and programs in MPE that can improve
productivity on HP 3000 systems. Get a free NewsWire "HP 3000 Always
Online" denim and suede cap - submit an MPE tip to Hidden Value. E-mail
your tips to rseybold@zilker.net, or fax them to 512-331-3807.
I'd like to use back-to-back DTC ports to permit inbound
telnet on my HP 3000 without a TAC. How can I do this?
With OpenView DTC Manager, a DTC port can be configured as one o
f
three types - terminal, printer, or host. If configured as a host port,
the port can be accessed via telnet to the DTC's IP address at a specific
TCP port number, as calculated by the following formula:
( ( ( 32 * dtc_board_number ) + dtc_port + 1 ) * 256 ) + 23
So, for example, for a DTC at IP address 199.8.123.123 to connec
t
to port 2 on board 0, you would use "telnet 199.8.123.123 791."
Alternate method: If you have additional IP addresses available
,
you can specify the desired address in the "Port Name" box of the DTCMGR
port config screen, and then the port will be telnet-accessible by a simple
IP address(or, presumably, by domain name if a DNS server is set up to
point a name to the appropriate address).
Once this port is accessible via telnet, if it is cabled to
another DTC portwhich is configured as a normal terminal, then the incoming
telnet can bepassed serially to a DTC> prompt, or if switching is not
enabled, pass directly to the default destination for that port. If the
destination is an
MPE/iX system, then we have effectively translated from telnet to
rs232 to AFCP, providing a means for a user with telnet but not NS/VT
capability to access the MPE/iX system from the network, without a Telnet
Access Card in the DTC.
Pay attention to these items while you're implementing the
solutions above:
The cable connecting the two DTC ports must be crossed (i.e.
null-modem, 2-3, 3-2, 7-7).
It's probably best to not use speed sensing on either port, but
rather force them both to 19200bps.
The serial link between DTC ports is the slowest link in the cha
in
here, so even if the telnet user has a T1 line, they'll only get 19200bps
throughput.
Only one telnet connection per port at a time. If a second user
tries to connect, they'll appear to get connected but will not receive any
prompts. If you set up more than one back-to-back pair and assign them the
same IP address, they should function as a pool, with the next available
port servicing each request (I haven't tried this though).
Some obvious security concerns are raised by this configuration.
NS/VT provides a certain level of 'security by obscurity', while telnet
access is more widely understood and available.
Disconnecting from the telnet session is not automatic. Upon
logging off the session will be left at a new logon prompt. Most telnet
clients use ^] to escape back to a telnet> prompt, from which a 'quit' or
'close' command usually terminates the connection. There may be a way to
get the DTC ports to signal each other via DTR drops on disconnect, but I
haven't found the right combination of DTCMGR settings and cable
configuration to make this work.
Jon Diercks
Programmer/Analyst, Anderson University
I have about 20 extract files created nightly that need to be
transferred from my HP 3000 (using Reflection) to my PC. Currently, I am
doing it by hand. Is there a way I can write a job to run it while the
extract files created? Those extract files are within the same group.
Neil Armstrong of the Robelle technical staff replies:
I can think of two ways of automating the download of some PC
files to a PC. You can put the HP3000 in control of automating this in a
job stream. This way you do not need a PC scheduler. I move files from our
NT server to our HP3000s, and move files from my Win95 PC to the 3000. The
method depends on the type of connection.
PC connected via RNS
If I had a PC connected to a LAN running Reflection for Network
Series I would turn on the FTP server function found in Reflection Network
Series and download the files with the following sample job stream.
!comment
!comment Download a file
!comment
!file ftptemp;temp
!echo exitonerror >> ftptemp
!echo binary >> ftptemp
!echo user test password >> ftptemp
!echo cd /download >> ftptemp
!echo put file1 file1.dat >> ftptemp
!echo quit >> ftptemp
!setvar ftplasterr 0
!run ftp.arpa.sys;info="pcname.domain.org";stdin=*ftptemp
!if ftplasterr <> 0 then
! showvar ftp@
! setjcw jcw fatal
!endif
!purge ftptemp,temp
You would have to configure a suitable username on the Reflection for
Network Series Server and keep it running overnight. Please keep in mind
that I have not tried this method to put files back onto a PC, but I do not
see why it should not work. I use this method to pick up files from a PC on
a nightly basis.
PCs connected serially
The details on how to do this are found under the :Reflect comma
nd
in your Qedit manual, but I thought you might like to see an example on how
to do this. I would use this method if the PC I wanted to download files to
was serially connected.
!job pcdownld,user.acct
!file qedcrt;dev=29
!run qedit.pub.robelle
file qedcrt;dev=58
continue
reflect receive file1.txt file1.data
exit
!eoj
Please remember that in order for this to work you must have
Reflection running in the background on the PC; the Reflection baud rate
must be the same as configured in MPE; and the PC must not be logged on at
the time.
I want my logon prompts for my MPE/iX system appear in upper and
lower case. When I make the change in SYSGEN it defaults to upper case no
matter what I type. How can the prompts I want?
In order to force SYSGEN to accept the lowercase or mixed-case
letters, you'll need to enclose the logon prompt string in double quotes.
In SYSGEN the commands look like this:
sysgen>MISC
misc>SY LOGONPROMPT="MyLogonPrompt"
To view your change, type the SHOW command at the misc prompt
inside SYSGEN. You'll see the following:
SYSTEM command parameter VALUE
LOGON PROMPT logonprompt MyLogonPrompt
Then issue the following commands:
misc>HOLD
misc>EXIT
sysgen>KEEP
Respond YES to the question to keep the configuration. Be sure t
o
shut down the system and bring it back up on a START NORECOVERY for the
change to take effect.