Newsgroups: comp.sys.mac.comm Path: utzoo!utgpu!cunews!bnrgate!bwdls61.bnr.ca!bnr.ca!bschmidt From: bschmidt@bnr.ca (Ben Schmidt) Subject: Re: MacTCP problem Message-ID: <1990Dec3.130757.4405@bwdls61.bnr.ca> References:<1990Nov30.205337.8345@ux1.cso.uiuc.edu> <693@nih-csl.nih.gov> Sender: usenet@bwdls61.bnr.ca (Use Net) Organization: Bell-Northern Research Date: Mon, 3 Dec 90 13:07:57 GMT In article brad@andros.cayman.com (Brad Parker) writes: >> In article <693@nih-csl.nih.gov> ken@helix.nih.gov (Ken Weeks) writes: >> >> I've been using NCSA Telnet to talk to my VAX, which is running a >> Telnet server. I recently "converted" from the embedded TCP driver >> version to the Mac TCP version. No problems at first...but as of late, >> I've noticed a severe, repeatable "hang" when I use the VMS "TYPE" >> commands, or list a long directory. Just that session hangs - I can log >> in again and kill it > I think the "mss" or maximum segment size of the TCP you are using is > too large for your gateway. Under NCSA you can set it (in the > config.tel file) to a small number like 512 which will not require > that you gateway fragment the packets. Under MacTCP, is it not settable, > and I think MacTCP 1.0 has a bug which causes it to guess wrong; (or at > least guess a number which causes you to need a gateway which will fragment > properly) > > I'll go out on a limb and guess that your mac is on localtalk and you're > using a gateway to get to the ethernet. If the gateway is a fastpath, it > may not support fragmentation of IP packets too big to be encapsulated > in a single localtalk packet (~600 bytes); If the gateway is a gatorbox, > you're software may be out of date as we used to have this problem > but fixed it. Yup. It sure sounds like a MacTCP 1.0 bug with MSS which affected Macs on LocalTalk. Are you using MacTCP 1.01? Ben Schmidt Bell-Northern Research, Ltd. Ph: (613) 763-3906 Information P.O. Box 3511, Station C FAX:(613) 763-3283 Technology Ottawa Canada K1Y 4H7 bschmidt@bnr.ca