Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!VAX.FTP.COM!jbvb From: jbvb@VAX.FTP.COM (James Van Bokkelen) Newsgroups: comp.protocols.tcp-ip.ibmpc Subject: Re: PCLAN/NetBIOS/TCP problem Message-ID: <8906201355.AA11103@vax.ftp.com> Date: 20 Jun 89 13:55:27 GMT References: <12199@netnews.upenn.edu> Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 37 Date: 19 Jun 89 21:16:56 GMT From: Anthony Olejnik Organization: University of Pennsylvania I'm having a problem with IBM's PCLAN program. The problem appears with both versions 1.2 and 1.3 (I don't know about earlier versions). I've noticed that when using either Ungermann-Bass PCNIUs (with Release 16.0 of their TCP/PC software) or WD8003E's (with PC/TCP v2.03 pl 1 software) the PCLAN server does not drop non-existent sessions. Clients who connect to the server are still "seen" by the server even after the PC is turned off. This presents a problem the next day when the same clients attempt to connect to the server again. If the server has available NETBIOS/TCP sessions, then the client is able to re-connect. However, this still leaves a non-existent session on the server end. If the server does not have any available NETBIOS/TCP sessions, then the client is not able to re-connect. I don't know why U-B is doing that: possible reasons include 1) not having implemented NETBIOS "session keepalives" or 2) not having implemented TCP "keepalives", or 3) a bug. As to why we do it, we had a problem in the "2.03 pl 1" kernel where one particular case of connection abort was treated as a normal close, and so the NETBIOS missed it. In my own testing here, I never noticed any problem with the PC LAN Program 1.2, because some other mechanism (I don't remember exactly what) cleaned up the connection when the client tried to mount the filesystem again. Both the kernel and the NETBIOS are up to Patch Level 3, with no known problems. Have you called our support people? We recommend the "/tsi:00" switch on the server. This is necessary if you want to use any PC/TCP utilities in the foreground. James B. VanBokkelen 26 Princess St., Wakefield, MA 01880 FTP Software Inc. voice: (617) 246-0900 fax: (617) 246-0901