> Support > NetWare Client32 and cc:Mail NFT Errors    8.4.x

NetWare Client32 and cc:Mail NFT Errors


Subject: Re[3]: Client32 and NW311 and NFT-errors
Author: Ron Herardian at GSS
Date: 06-05-96 01:32

Jan,

Since you have NFT errors from varying sources, it sounds like you may have some underlying system design or network issues. Note that once an actual corruption has occurred, every cc:Mail Router, client, and gateway may report and "NFT error reading." This is because there is a bad CRC in the database, perhaps it's just the CRC, perhaps there is a real corruption.

If there is a real corruption, it may be trivial or very serious depending on where in the post office the corruption is. With some minor corruptions, you could run CHKSTAT with the "NFT/C" parameter and bring the PO back on line immediately. This is never recommended. You wouldn't know the nature of the problem unless you ran ANALYZE. Of course, most minor problems are corrected by CHKSTAT with the "DIAGNOSTICS/R" parameter. Remember that CHKSTAT with the "NFT/C" parameter does NOT fix anything -- it merely recalculates the CRCs whether there is a real corruption or not.

If you see many entries for "NFT Error reading" from the same file and offset (CLANDATA sector 0, for example), then you already have a corruption or at least a bad CRC. In the log, go back before these redundant errors began. Find the last error before the stream of "NFT Error reading" entries. Often, you'll find an error writing or verifying that kicks off the stream of NFT Errors reading.

To analyze NFT errors more carefully, determine the location of the machines producing the errors on a detailed network diagram. Check if they are on the same segment, sharing a common hub, routed through a common router, crossing a common backbone, etc.. For the cc:Mail Router that keeps appearing in the log, check if it's coming in over your WAN. This is a common system design error: mapping network drives over a WAN and using Type I Router connections rather than Type II connections.

You say that you don't have a traffic problem because users are on a 20-user 16Mbps Token Ring. I want to ask, where is the server and what is the route to it in your physical LAN? Is the server across a WAN from the users? Is it on the other side of an overloaded Router? Is traffic from your WAN traversing the seemingly quiet 20-user Ring? Perhaps there are 700 SAP broadcasts from connected networks every 60 seconds. The only way you can know is by measuring and monitoring traffic and network errors on each segment or Ring from the problem users to the server.

I am also wondering what version of cc:Mail for Windows you have. If you are getting significant numbers of users reporting GPFs, you need to look for a pattern in the error: a certian time of day; a specific server; a specific area of the network.

I have found that there are sometimes serious traffic problems or extremely high server utilization when large numbers of users are reporting NFT and Mail Engine errors. I see widespread GPFs almost never, at least not with recent versions of the cc:Mail for Windows. Do you have a standard workstation configuration? What is it? The GPFs may be unrelated to the NFT errors in which case we should be looking at the Windows workstations. How are the Windows resources (GDI, USER, and system memory)?

I commonly find a series of related but not obvious system design problems where there is a laundry list of errors. In your case the list is NFT errors, cc:Mail for Windows GPFs, and actual post office corruptions. I think you should first do more to isolate the problems you are seeing and second review your system design and deployment of cc:Mail.

Ron

--

Subject: Re[2]: Client32 and NW311 and NFT-errors
Author: janneb@jbdata.se at INTERNET_ROUTER
Date: 06-05-96 00:44

Ron,

For every time the PO has been shut down I've looked in NFTERROR.LOG. The first row indicates that one of the WIN95-users (actually the only one logged on) gets a NFT Error. No warning, an error directly. In row two there's an error from VIM 2.07 (which I guess is LFS). From row 3 and some 10000's row down is the routers who constantly retries the PO. The Win3.1-users are using WNOTIFY, which doesn't behave too nicely when a NFT Error is produced (GPF), so there is no indication of their problems in NFTERROR.LOG. I'm very much sure that this is directly caused by the Win95 Installation. I haven't had one single NFT-error (OK, some warnings now and then) for three years but this started to happen the first day after the Win95 Installation. The only oddity in this LAN is that the PO is on a 3.11-server with PBURST loaded. A look in the LAN Statistics shows some PBURST Errors and for now I've turned PBURST off and hopefully the PO will live over the day. Saturation of the network isn't probable since this PO is on a T/R 16 Mb with approx 20 active users a ring.

Jan

BTW, there were 2 shutdown yesterday.

Subject: Re: Client32 and NW311 and NFT-errors
Author: rherardi@GSSNET.COM at Internet-JB
Date: 1996-06-04 19.58

Jan,

This is where a close look at the NFTERROR.LOG would be useful. You need to know where the errors are coming from (what users or machines) and what type of error it is. The Client32 problem commonly results in errors reading CLANDATA with small number of attempts but there is not necessarily an actual corruption of the database.

To cause NFT errors in the database there must be errors writing or verifying. These are a serious problem usually caused by faulty network or server hardware or related to other network problems such as saturation of the network or extremely high server utilization. Where there are system design problems, the cc:Mail system may be vulnerable to WAN issues as well, such as network routing problems.

In your note, there no evidence is cited indicating that the Client32 workstations are the cause of the NFT errors. Yiou should follow the usual procedure for troubleshooting NFT errors.

Ron

--


Subject: Client32 and NW311 and NFT-errors
Author: "cc:Mail Interest Group" <CCMAIL-L@LISTSERV.OKSTATE.EDU> at INTERNET
Date: 06-04-96 07:25

Hi,

I have a problem with a PO hosted on a NW3.11-server. The server is using lslenh and the latest (LANDRV5) Landrivers. Two of the users are using Win95 with the patched Client32 and Opportunistic Locking and Pburst turned off. Five times since last Friday has the PO went down because of NFT-errors. Chkstat has been able to fix it with /NFT/C. My question is: Could the problems be caused by some incompatibilities between Client32 and NW3.11? Has anyone of you, any experience in this?

Thanks for any tips

Jan Bojeryd
- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Jan Bojeryd, JB Datakonsult AB E-Mail: janneb@jbdata.se
Kullavagen 3 Phone: +46-910-77 67 31
931 38 SKELLEFTEA, SWEDEN Fax: +46-910-77 67 31
WWW: http://www.jbdata.se Mobile: +46-70-523 34 45
- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Jan Bojeryd, JB Datakonsult AB E-Mail: janneb@jbdata.se
Kullavagen 3 Phone: +46-910-77 67 31
931 38 SKELLEFTEA, SWEDEN Fax: +46-910-77 67 31
WWW: http://www.jbdata.se Mobile: +46-70-523 34 45
- - - - - - - - - - - - - - - - - - - - - - - - - - - - -


 
Messaging, Directory Services, Groupware


©1995-2005 by Global System Services Corporation (GSS). Portions of this material are copyright ©1995-1999 by Ron Herardian