Expand vs. TCP/IP
John
in favor of TCP/IP?
I've got a very small system, one K2000, one K100, both on D45, and use
expand for real-time disaster recovery logging only. If the running
application will allow logging via TCP/IP, I see no reason to continue
the cost of the Expand line.
There is only me in the IT department, and I can work without Expand.
I'm also aware of the problems with a downed network, which are of
minimal concern to this application.
Any thoughts will be appreciated.
Alan Gillson
D45 and works really well...its also a pre-req if you have any plans to have
S series boxes in your network.
ALAN
Fred S.
>Is EXPAND required for Tandem-to-Tandem communication, or can I dump it
>in favor of TCP/IP?
>
Only if you want the Tandems to use Expand - i.e. able to access each
other's processes and file systems using \node names.
>I've got a very small system, one K2000, one K100, both on D45, and use
>expand for real-time disaster recovery logging only. If the running
>application will allow logging via TCP/IP, I see no reason to continue
>the cost of the Expand line.
>
You can run "Expand over IP" - I have heard that it is somewhat
CPU-intensive, but it sounds like what you're looking for.
Dan Parker
> Is EXPAND required for Tandem-to-Tandem communication, or can I dump it
> in favor of TCP/IP?
It depends on what you mean by "Tandem-to-Tandem communication". In the
simplest sense, programs running on two NSK nodes can communicate with one
another via any of the many comm protocols currently supported by
Tandem...including TCP/IP. But then you have to code to use that protocol
specifically (or some product/process which serves to front-end the
protocol for you.) You also lose out on all of the inherent
interconnectivity features of a Tandem network, such as the ability of
processes on one node to access processes/devices/files on another node
using the same "OPEN/READ/WRITE/CLOSE" mechanism you would use on local
entities. Not to mention the myriad of NSK facilities that will no longer
be able to communicate across nodes.
> I've got a very small system, one K2000, one K100, both on D45, and use
> expand for real-time disaster recovery logging only. If the running
> application will allow logging via TCP/IP, I see no reason to continue
> the cost of the Expand line.
What cost are you referring to here that will be recovered by substituting
TCP/IP? Have you considered Expand over IP?
Dean Malone
dedicated link. This will allow you to use expand without changing the
applications that use expand. Good luck.
John wrote:
> Is EXPAND required for Tandem-to-Tandem communication, or can I dump it
> in favor of TCP/IP?
>
> I've got a very small system, one K2000, one K100, both on D45, and use
> expand for real-time disaster recovery logging only. If the running
> application will allow logging via TCP/IP, I see no reason to continue
> the cost of the Expand line.
>
Douglas I. Chmara
Ditto to that. Expand is invaluable to us (you don't transmit anything,
you just use files where they are and Guardian does the rest) but we do
it across the TCP/IP network, not the direct lines, anymore. Expand-over-
Lan (must be same subnet - we successfully bridged across a comm line but
it was still the same subnet even though remote) has been around for a
while (any supported release). We still keep our local direct links as
backup because they are there and paid for, but Expand/Lan is better and
much faster. If your Expand lines are expensive, you probably don't fit
all on one subnet, so you would need Expand-over-IP (only D4x and above,
but you are D45 so that's okay). Configured essentially the same as
Expand-over-Lan, but works at IP, rather than MAC, level, so the LAN
restriction is relieved. BTW, if your disaster logging is RDF, it can
only use Expand as its link. Good luck.