freeman-andrew@CS.YALE.EDU (Andrew C. Freeman) (09/15/89)
We need some advice on a couple of issues. Any comments or information
would be greatly appreciated.
Location 1: Sun 4/390s running a Sybase server
Locations 2,3,4,5: Small Sun networks across the country
What we hope to accomplish is the following:
Transparent client access from locations 2-5 to the server at
location 1 (i.e. ability to use Sybase as if we were one local net),
as well as telnet, etc.
At our disposal is an SNA network connecting all the sites. We would prefer
to use it but if there are other cost effective ways we will certainly
consider them. The real questions here are whether TCP/IP over SNA is
possible/feasible/tolerable and whether Sybase DB-library functions well
over an internet
A side issue involves SNA on Sun. Can we support a user (either logged in
via telnet to the server or directly from locations 2-5) who wants a
terminal session to an IBM host on the SNA network and can we support
application to application from the Sun server to the IBM host.
Thanks in advance for those copious, informative replies. Please reply by
mail and include a telephone number if you would'nt mind a phone call. Also,
I realize that these topics may be fairly standard to some but please, don't
let my ignorance dissuade you from replying.
Thanks,
Andrew
philf@xymox.com (Phil Fernandez) (09/17/89)
In article <72701@yale-celray.yale.UUCP> you write: >... >At our disposal is an SNA network connecting all the sites. We would prefer >to use it but if there are other cost effective ways we will certainly >consider them. The real questions here are whether TCP/IP over SNA is >possible/feasible/tolerable and whether Sybase DB-library functions well >over an internet I can give you a couple of answers here, from different experiences. I bought and installed Sybase for the main computing center at Stanford prior to recently re-joining the "real world" here at Metaphor Computer Systems. Stanford was running Sybase V4 on a Sun 4/280, supporting a bunch of clients around our campus TCP/IP Ethernet (SUNet). SUNet uses a backbone and spine topology, all 10Mbps, using primarily cisco Systems internetwork routers. Typically the clients were running on Sun 3/60 workstations. Some of our Sybase DB-Lib clients were 2 or 3 routers away from the Sybase server, and it all seemed to work pretty well. In this case, Sybase worked very well over the Stanford internet. I would easliy recommend production use in this environment. I'm less sure about using an SNA network as an intermediate. I can come at this from a different direction. I have no experience with TCP/IP thru an SNA net, but here at Metaphor, we have a product that performs XNS internetwork routing via an SNA network. we use this internetwork capability for a client/server model data base query system (but not Sybase). Our model is probably less "interactive" that a typical Sybase c/s application would be, but it still doesn't work very well. That is, we experience rotten performance across the SNA net. Typical SNA networks can have relatively long delay times (on the order of a couple of seconds), and this can be a problem with a highly interactive application. Our datagram routing through SNA is pretty optimized and is "state of the art" -- we route via an SNA LU6.2/PU2.1 connection, which is the best we're going to do at this time. So, I'd be careful... pmf +-----------------------------+----------------------------------------------+ | Phil Fernandez | philf@metaphor.com | | | ...!decwrl!metaphor!philf | | Metaphor Computer Systems |"Does the mind rule the body, or does the body| | Mountain View, CA | rule the mind? I dunno..." - Morrissey | +-----------------------------+----------------------------------------------+