cro@cs.arizona.edu (Charles R. Oldham) (12/03/89)
Help!
I help manage a Macintosh lab here on campus that contains 41 Macintosh SEs,
10 SE/30s, 2 LaserWriter II NTs, and a Mac II as a file server and print
spooler. All machines are connected to the II via PhoneNet/AppleTalk. Up
until last week we only had 26 machines in this lab; then we doubled that. I
connected the network after the installation and found everything OK except
the last four machines on the end of the network daisy-chain won't print
to the spooler! The spoolers come up fine on the Chooser, as does the file
server, but when printing, AppleShare Print Server shows a job beginning to
spool, but never finishes. In fact, it doesn't even get as far as giving
a Document name or a Chooser name in the print queue.
Our lab is laid out in the following manner:
Terminator---16 SEs---10 SE/30s---MacII---LW---LW---20 SEs---4 SEs---Terminator
LONG Cable ^ Problem Machines ^
Have we surpassed the limits of a PhoneNet Network? What are they anyway?
What can we do about it? Any help would be appreciated.
Thanks in Advance.
/*---------------------------------------------------------------------------*/
/*Charles R. (C. R.) Oldham | Bitnet: OLDHAM@ARIZRVAX */
/*Department of Instructional Computing | Internet: */
/*Ctr. for Computing Information and Technology| oldham@rvax.ccit.arizona.edu*/
/*University of Arizona | cro@caslon.cs.arizona.edu */
/*Tucson, Arizona | "He's dead, Jim"--McCoy */
/*---------------------------------------------------------------------------*/vallon@sbmiclr.Berkeley.EDU (Justin Vallon) (12/05/89)
> [ A PhoneNet net (?) with 50 nodes. Last 4 SE's on right can't spool. ] > > Terminator---16 SEs---10 SE/30s---MacII---LW---LW---20 SEs---4 SEs---Terminator > LONG Cable ^ Problem Machines ^ > > Have we surpassed the limits of a PhoneNet Network? What are they anyway? > What can we do about it? Any help would be appreciated. The limit of PhoneNet is 3000 feet. I would find it hard to believe that your lab has 3000 feet of wire (that about 3/5 mile). The problem might be that you've got too many nodes on the network. It seems as though the 4 SE's are further (counting the number of nodes the signal goes through) from the Mac II than all others. You might want to try buying some repeaters (two would probably be enough) to boost the signal. Or, think about getting a bridge. Although, traffic would probably not be reduced, because most of the traffic is probably directed to the Mac II & LW's. Not much traffic between SE's, right? I'm assuming that this is a "public" cluster with few AppleTalk applications. > > Thanks in Advance. > > /*---------------------------------------------------------------------------*/ > /*Charles R. (C. R.) Oldham | Bitnet: OLDHAM@ARIZRVAX */ > /*Department of Instructional Computing | Internet: */ > /*Ctr. for Computing Information and Technology| oldham@rvax.ccit.arizona.edu*/ > /*University of Arizona | cro@caslon.cs.arizona.edu */ > /*Tucson, Arizona | "He's dead, Jim"--McCoy */ > /*---------------------------------------------------------------------------*/
horan@batcomputer.tn.cornell.edu (Frederick Horan) (12/12/89)
There are a few possible problems. The first problem is that there are to many nodes on that line as has already been mentioned. There are other potential problems though that I would like to hear from others about such as: what happens when different kinds of cable are used between nodes. Is there a reflectance problem? Also I would like to hear about the problem of capacitance. We have been using old localtalk line with modular connectors and I am concerned that the shielding in the cable increases the capacitance per foot above that of twisted pair cable. Fred Horan (horan@tcgould.tn.cornell.edu)