[Info-vax] terminal servers etc

[Johnny Billquist]

Others have already responded, but I'll add one more voice anyway...

On 2013-01-05 19:16, Phillip Helbig---undress to reply wrote:
> I would like to connect some real terminals far away from my cluster to
> a LAT service on the cluster so that I can hit RETURN on the terminal
> and one of the nodes will offer the login prompt.  If I have the basic
> idea correct, I can connect the terminals to a terminal server via a
> serial connection then connect the terminal server to the LAN where it
> can talk to the cluster via TCPIP or LAT.
>
> I've used a similar setup, years ago, but have no idea how it was set
> up.
>
> Speed is not an issue since I can't type much faster than 100 b/s.  :-)
>
> Some questions (note: I'm not looking for actual instructions; I'll look
> them up if I decide to go this route):
>
> How difficult is this to set up on the VMS side?

Not hard. Script for doing this have already been mentioned,

> Is LAT preferable (easier, better) than TCPIP?

It might be that for load sharing features, you want LAT. Do a cluster 
have a cluster-wide IP address that can be used, which ends up at any of 
the cluster nodes? Otherwise you'll need explicit connections to each 
node, which is less flexible than the LAT solution.

> I have stuff like DECserver 90TL, DECserver 90M.  Will this do what I
> want?  (I also have some DECserver 200MC and 250 but I assume the 90s
> are the better choice here.)

They all work equally well from a LAT point of view, network wise, and 
so on. Pick the one you have/prefer.

> The DECrepeater 90T is functionally equivalent to a 10 Mb/s hub (but
> amplifies the signal, hence a repeater and not a hub), right?

Essentially, yes. Not sure you can correctly describe it as an 
"amplifier", but the end result is pretty much that.

> T is TCPIP, L is LAT, TL is both, M is both and more?  Since a hub or
> repeater is essentially a dumb device, why can't it handle all protocols
> as long as the wiring is correct?

I doubt the lettering stands for anything like that. A repeater repeats 
ethernet frames. Not any specific protocol.

> Is the only network connection on the server the BNC coax connector?  If
> so, I'll probably need one of the repeaters in order to connect this to
> a twisted-pair network.  I have both standalone server and repeater as
> well as some which connect to a backplane (and have the backplane as
> well).  Will the backplane provide a network connection between server
> and repeater?  (If so, I might be able to avoid BNC.)

On the DS200, you have thinwire and AUI. There are AUI adaptors that 
give you TP as well. No need for thinwire. This is how I connect my DS300.

	Johnny

-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol