Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!cs.utexas.edu!sun-barr!newstop!eastapps!hinode!geoff From: geoff@hinode.East.Sun.COM (Geoff Arnold @ Sun BOS - R.H. coast near the top) Newsgroups: comp.protocols.nfs Subject: Re: PCNFSD V2 (part 1 of 2) Message-ID: <6219@eastapps.East.Sun.COM> Date: 18 May 91 13:30:53 GMT References: <5883@eastapps.East.Sun.COM> Sender: news@East.Sun.COM Reply-To: geoff@east.sun.com (Geoff Arnold @ Sun BOS - R.H. coast near the top) Organization: Sun Microsystems PC-NFS Engineering Lines: 51 Quoth rossc@extro.ucc.su.OZ.AU (Ross Cartlidge) (in ): #Is this compatible with PC/NFS 3.5? The V2 PCNFSD server includes support for both V1 and V2 of the PCNFSD protocol. Given that, it should interoperate with any client which worked with the old PCNFSD server (using V1 protocol). Obviously such a client will not issue V2 requests and will thus not get the benefit of the added functionality. However... In one respect the new PCNFSD is not 100% compatible with PC-NFS 3.5 or earlier: it's stricter, and PC-NFS doesn't handle the newly-possible errors correctly in all cases. In the past, PCNFSD would accept a request to initialize printing on any printer name, valid or not. It always passed back a spool path, and PC-NFS could mount it up and drop spool files in there to its heart's content. When PCNFSD received a request to print one of these files, it would ship a request of to lpr, and let it figure out whether the name was valid. For the V2 protocol revision, it was decided to include a mechanism to determine which printers were acessible on a given PCNFSD server host. (This was to allow people to build browsers'n'stuff...) PCNFSD builds this list as needed and then validates any print request to make sure the printer name is on the list. Here's the problem: the list does not include all of the aliases for the various printers: it simply includes the names as returned by "lpstat". Thus if you have a printer "pcdslw", with an alias of "lw2", in your printcap, the behaviour of PC-NFS 3.5 will differ depending on which PCNFSD is running. With the old PCNFSD, you can mount and print to "pcdslw" OR "lw2" without any problem. With the new PCNFSD, you can mount and print to "pcdslw". If you try to mount "lw2", PCNFSD will return an error code and a null path. PC-NFS 3.5 may ignore the error code and try to mount the null path, which maps to the root. (You learn something new every day! Should that be legal????) If the root is exported, everything looks fine until you try to print, and fail because you can't write into the spool directory! (If you suspect this is happening, try "DIR T:" or similar: if you see "vmunix" in the list, that's a good clue....:-) So, if you choose to run the new PCNFSD, be careful with your printer names. If you do, it should all work fine. Geoff -- Geoff Arnold, PC-NFS architect, Sun Microsystems. (geoff@East.Sun.COM) -- ------------------------------------------------------------------------------ -- Sun Microsystems PC Distributed Systems ... -- -- ... soon to be a part of SunTech (stay tuned for details) --