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Xref: sserve comp.os.386bsd.announce:371 comp.answers:5261 news.answers:22224 Path: sserve!newshost.anu.edu.au!harbinger.cc.monash.edu.au!msuinfo!agate!howland.reston.ans.net!europa.eng.gtefsd.com!MathWorks.Com!news.duke.edu!godot.cc.duq.edu!nntp.club.cc.cmu.edu!news.mic.ucla.edu!ux1.lmu.edu!s069.infonet.net!s069.infonet.net!not-for-mail From: burgess@s069.infonet.net (Dave Burgess) Newsgroups: comp.os.386bsd.announce,comp.answers,news.answers Subject: [comp.os.386bsd] BNR/2 derived BSD for PCs FAQ (Part 7 of 10) Followup-To: comp.os.386bsd.misc Date: 3 Jun 1994 22:45:33 -0000 Organization: Dave's House in Omaha Lines: 564 Approved: news-answers-request@MIT.Edu Distribution: world Expires: 06/21/94 Message-ID: <386bsd-faq-7-770683512@s069.infonet.net> References: <386bsd-faq-1-770683512@s069.infonet.net> Reply-To: burgess@s069.infonet.net (386bsd FAQ Maintainer) NNTP-Posting-Host: s069.infonet.net Posted-By: auto-faq 2.4 Archive-name: 386bsd-faq/part7 Section 6. (Interaction with MS-DOS) 6.0 Working with DOS and BNR/2 related software. This section is designed to cover some of the more common problems that DOS will have when interacting with BNR/2. There are other sections of the FAQ that deal with indirectly with this . Try looking in sections 0, 1, and 2 to see if something in there (particularly when talking about DOS and *BSD coexisting on a single drive). 6.1 Formatting a floppy There is a rumor that floppy formatting either is possible or was possible at one time. If you see any software or FTP sites with anything about this, please contact burgess@hrd769.brooks.af.mil and I will make sure it gets updated in here. There was a set of patches that were developed to allow floppy formatting. They are not currently included in any of the *BSD systems. I have actually applied the patches for floppy formatting here on NetBSD, and they seem to work just fine. The fdformat program could use some work, but seems to work OK. According to the author, similar patches are available for NetBSD and the original 386BSD. Presumably, FreeBSD patches can't be too far behind. The package that I used here was posted in comp.os.386bsd.* somewhere. I think that it is available by anonymous FTP from hrd769.brooks.af.mil. If not, E-Mail me at burgess@hrd769.brooks.af.mil and I will mail you a tar file with the stuff that i have available. 6.2 Sharing the Disk with MS-DOS There are a myriad of questions about how to share a disk between 386bsd and MS-DOS. They all boils down to one of the <n> following questions: 1) How can I partition my drive for both MS-DOS and 386bsd? 2) I can install using the whole disk, but I can't install when I try to share the drive between 386bsd and MS-DOS. Why? 3) I can use either MS-DOS or 386BSD on my hard drive, but shutdown -todos doesn't seem to work. 6.2.1 How can I partition my drive to support both MS-DOS and *bsd? NOTE: Before attempting to install *bsd on a computer with an active DOS partition, ALWAYS back up your hard drive. No one on the net, no matter how talented, can help you recover a hosed MS-DOS file system. If you lose all of your data, it is YOUR fault. During the install phase, you need to have un-allocated space left on your disk drive. This allows the install program to correctly install the *bsd partition in the partition table and DOS to peacefully co-exist with *bsd. If you do not have any space available on your hard drive, you will not be able to install both. Re-fdisk your hard drive and make sure you have left un-allocated space in the partition table. This WILL wipe out your DOS partition - Permanently. Even though the partition table procedure above may have worked, there are still no guarantees that your system will boot after the install. This problem most often manifests itself as one of the endless reboot problems. You would normally be able to boot DOS from the hard disk, but not *bsd (once that partition is marked as active). Once the partition table has been correctly defined with both DOS and *bsd, there can still be problem. One of the most common is that the disk drive works in some sort of translation mode. This is particularly common with drives that physically have more than 1024 cylinders. DOS cannot access a drive with more than 1024 cylinders. Translation mode will have to be turned off, usually by redefining your hard drive in SETUP as one of the user definable types. This change will normally trash your hard drive, or at least render your DOS partition unreadable. The solution to this problem is to install *bsd at the end of the hard drive. While DOS cannot use cylinders above 1024, *bsd has no such limitations, once it has booted. During the boot-up phase, some of the newer boot blocks will refer to the BIOS for some services. Specifically, the disk is checked for a bad sector map on the last track. Since the BIOS cannot deal with cylinders higher than 1024, your bad sector map will be incorrectly identified as 1023 if the number of cylinders is larger than that. This problem is being worked on, and I hope to change this section with better news later. NOTE: The only people that this problem will effect are those MFM and ESDI users that have drives with more than 1023 tracks. While drives of this type are not the overwhelming majority, neither are they an anomoly. People are working on it. As an example, if your hard disk physically has 8 heads, 16 sectors per track, and 2000 cylinders (128M); you MUST use some sort of disk translation in order to use the entire drive. An obvious geometry for this drive (for DOS) would be 16 heads, 16 sectors, and 1000 cylinders. Unfortunately, *bsd operates using the disk drives native geometry as reported during the probe phase of boot up. This will probably be 8/16/2000, and will NOT agree with your translated disk geometry. This causes an endless reboot cycle. If you change the geometry so that the drive agrees with the disklabel, your DOS partition is toast. The best way to operate in this case would be to (for example) split the disk in half. That leaves 64M for DOS, using a geometry of 8 heads, 16 sectors per track, and the first 1000 cylinders for DOS. The second 1000 cylinders could then safely be used for *bsd. The DOS partition table may even be capable of showing this partition as it actually exists. Luke Mewburn <zak@rmit.edu.au> has provided the following tutorial on using the pfdisk program and making your *bsd/NetBSD partitions peacefully coexist with DOS. While this is kind of a 'cookbook' approach, please keep in mind that this is probably easily transferrable to all BNR derived Unices. Getting NetBSD 0.8 to coexist with DOS. Written 930510 by Luke Mewburn <zak@rmit.edu.au> NetBSD can be made to happily co-exist with DOS if its install program knows how to modify the partition table. This assumes that you have access to a program which enables you to edit the partition table of your hard drive (such as Norton Utilities, or pfdisk). When you partition your hard drive, you will probably have a large partition in which you wish to place NetBSD. This has to have the partition ID of 165d (or 0xA5). To change this, you can use the 'Partition Edit' section of Norton's, or you can use pfdisk. This document will go into more detail on how to use pfdisk, as it's freely available. I'll use my personal drive specifications in the following example. It is a 1001 cylinder, 15 trk/cyl, 17 sec/trk, 125MB drive. I low-level formatted it, and used fdisk on a MS-DOS 5.0 boot disk to create a primary partition '1' of 32MB, and an extended partition '2' of 93MB. I formatted the drive with format c: /s to give myself a bootstrap for DOS (much faster than floppies :), but this isn't that necessary. Now, the next stage... Running pfdisk 0 (to access my first (and only :) HD) came up with something like: For help, enter: '?' pfdisk> At the prompt, enter 'l' to list partitions, giving (in my case), something like: # Partition table on device: 0 geometry 1000 15 17 (cyls heads sectors) # ID First(cyl) Last(cyl) Name # start, length (sectors) 1 4 0 256 DOS16 # 17, 65518 2 0 257 999 unkno # 65535, 189465 3 0 0 0 empty # 0, 0 4 0 0 0 empty # 0, 0 active: 0 (none) (Note that there is 1 cylinder less - the last one is, I think, for the IDE controller to use when auto-mapping dud sectors out.) Now, we want to change the type of #2 (the prospective NetBSD partition) to 165. You can obtain a list of known IDs by selecting 'I'. Depending on the version of pfdisk you have, 165 may or may not be known. This doesn't matter too much either way. To get the NetBSD install program to use the 2nd partition, I would enter: pfdisk> 2 165 257 999 Another 'l' to list partitions would show that the entry for partition 2 will either look like one of the following (depending on whether pfdisk knows about the 386bsd partition type or not): 2 165 257 999 unkno # 65535, 189465 or 2 165 257 999 386BS # 65535, 189465 You could set the active partition with 'a 2' if you want NetBSD to always boot, but I personally recommend that you obtain a copy of OS-BS 1.35 or BOOTEASY to save you the hassle of running fdisk or pfdisk every time you wish to swap system types. To complete everything off, do 'w' to write out the info (once you're sure it's correct! :), and 'q' to quit the program. Well, I hope that is useful to someone. Comments can be directed to the author (Email: <zak@rmit.edu.au>). 6.2.2 I can install using the whole disk, but I can't install when I try to share the drive between 386bsd and MS-DOS. Why? This is an extension of the question above. The most common reason for this is, once again, disk translation problems. If the disklabel does not agree with the disk geometry, the install will fail. Other incarnations of this problem are that you can install DOS, then 386bsd, and DOS will be hosed, or vice versa. There are more than a couple of people who will blithely suggest that this is a good thing, and you should install 386bsd exclusively, job not withstanding. 6.2.3 I can use either MS-DOS or 386BSD on my hard drive, but shutdown -todos doesn't seem to work. There is a known bug in shutdown that prevents the -todos option from working as advertised on all but the smallest DOS partitions. Many people have reported some success while using a very small (less than 32M) DOS partition as the first partition. There is a utility available for 386bsd which operates very much like the MS-DOS fdisk partitioning program. You can use this program to mark the DOS partition active from 386bsd. A similar procedure is used (fdisk in DOS) to mark the 386bsd partition as the active boot partition. Boot managers are also an excellent investment for those individuals that need to boot both DOS and 386BSD. 6.2.4 Is there any hope of ever running MS-DOS applications under any of the free BSD systems? There is currently a project in development to port the Windows program exvironment to Linux and the *BSD systems. Here is an excerpt from the original message announcing the project: As many of you already know, we are in the process of creating a Windows emulator. This emulator is similar to Sun's Wabi product, but is being developed completely independent of them. Many of you are anxious to hear the latest status of the project. I have created a mailing list for those of you. To join the list, simply send mail to: wine-project-info@amscons.com If your mailing address is not easy to deduce from the mail headers, then place the following line in the body of the message that you send. Reply-To: youraddress@yourmachine where youraddress@yourmachine should be replaced by your actual mailing address. 6.3 Accessing the MS-DOS filesystem One of the most common MS-DOS related questions (with the possible exception of 6.2 above) is how to access the DOS disk partitions from 386bsd. One way is to modify mtools so that it recognizes your DOS partition. This solution is provided by Jim Paradis (paradis@sousa.ltn.dec.com): -------------------------------------------------------------------- To build a /usr/othersrc/public/mtools.2.0.5/devices.c file that lets you access the DOS partition, you need to know the byte offset of the DOS partition from the start of the hard disk. You would then add an entry to the devices[] array as follows: {'C', "/dev/wd0d", <byte-offset>L, 16, 0, (int (*) ()) 0, 0, 0, 0}, So, f'rinstance, if your DOS partition starts at the beginning of the disk, you'd have: {'C', "/dev/wd0d", 0L, 16, 0, (int (*) ()) 0, 0, 0, 0}, On the other hand, if your DOS partition starts 32MB into the disk, you'd say something like: {'C', "/dev/wd0d", (32768L * 1024L), 16, 0, (int (*) ()) 0, 0, 0, 0}, -------------------------------------------------------------------- Of course, this is both the hard and VERY non-portable way of solving this problem. An easier way would be to add PCFS to your 386bsd/NetBSD system. Both the PC File system and PC Network File System (PC-NFS) code has been ported to 386bsd/NetBSD/FreeBSD. These are available from several sources, including the patchkit. The instructions for using PCFS with 386BSD are provided by Scott Miles <gt1679c@prism.gatech.EDU>. What would probably be easier would be to add a partition to the disklabel for your DOS drive and then just mount it with PCFS. I don't know if it's in the FAQ now, I haven't read it for a while, but this is what I did: 1) run 'fdisk' and write down the DOS partition info for the start and size that it gives you. 2) disklabel -e -r /dev/<raw device> - Add 1 to the '# partitions:', and then add another line for the DOS partition . Mine went in after e: as f: 130977 63 unused 0 0 # (Cyl. 0*- 129*) (Ed.Note: The unused should be something else, although I really couldn't tell you what. MSDOS is a recognized partition type name, maybe that should be used. Also, make sure that your c: and d: partitions do not overlap this area. h: might be a better partition letter to use; that way the MSDOS partition is graphically separate from the rest of the BSD partitions. DO NOT USE a:, b:, c:, or d: for your DOS partition. These are RESERVED for your BSD system and any attempt to use these for anything but what BSD uses them for will result in a completely hosed, totally dead, absolutely screwed up file system. You have been warned! ) 3) Add a line to /etc/fstab if you want it mounted automatically. Mine is: /dev/wd0f /dos pcfs rw 1 2 Otherwise, just mount -t pcfs /dev/<part> /<dir> Mount has other options that may improve performance or increase security for your system. See 'man mount' for more information about mounting your system read-only and other advanced features. In addition to this, Jordan Hubbard has provided us with the following description for mounting the DOS partition specifically from FreeBSD: How to mount your DOS partition from FreeBSD 1. First, be root. The following won't work as an ordinary user. 2. Second, use 'fdisk' to see where your DOS partition starts. It will be labeled as type DOS. On my system, 'fdisk /dev/sd0d' produces the following: ... (extraneous output, not of interest) ... The data for partition 0 is: sysid 6,(Primary 'big' DOS (> 32MB)) start 32, size 306400 (149 Meg), flag 0 beg: cyl 0/ sector 1/ head 1; end: cyl 149/ sector 32/ head 39 This shows me that my DOS partition starts at sector 32, and is 306400 (512 byte) sectors long. NOTE: If you're trying to mount a DOS `EXTENDED' partition, then you need to add `32' to this start address you got from fdisk in subsequent calculations, I.E. in the above example (assuming it was an EXTENDED partition rather than the Primary), you'd use `start 64, size 306400'. [Ed.Note. This example assumes a SCSI disk. For disks with a number of sectors per track which is different than 32, you will probably see the 32s above replaced with your number of sectors per track. ] 3. Next, using this information, you craft a new disk entry in your /etc/disktab file that assigns one of your unused "UNIX" partitions to this DOS region. Again, using my system as a default, you see I've created: disk0|DEC 5501:\ :ty=winchester:dt=SCSI:se#512:nt#8:ns#256:nc#1001:rm#3600:\ :pa#956416:oa#307200:ba#8192:fa#1024:ta=4.2BSD:\ :pb#131072:ob#1263616:tb=swap:\ :pc#1087488:oc#307200:tc=UNUSED:\ :pe#306400:oe#32:te=MSDOS: As you can see, partition 'e' now points to the DOS partition as pointed out by fdisk. [Ed.Note again. Remember what I said about the 32 above...] 4. Now we have to actually stick the label on the disk, which is done with disklabel. Using my example, this would be: disklabel -r -w sd0 disk0 SCSI /usr/mdec/sdboot /usr/mdec/bootsd 5. Reboot your system to see the new disk label. 6. Mount the DOS partition. I do: mount -t pcfs /dev/sd0e /dos_c Where /dos_c is just a convenient directory to mount it. 7. You're set! With the exception that the '-t' option is msdos in NetBSD, these instructions seem to work with the same facility for NetBSD. I also received a note a couple of weeks ago (that I promptly deleted because I new that I would remember what it said) that DOS extended partitions are readable if you skip the first 'n' blocks in your computations (where 'n' is your number of sectors per track). This way, you skip over the 'new' part of the DOS file system. That means that insted of the oe:32 above, you would need an oe:48 instead. Also remember that the compressed file system in DOS 6 will probably be completely greek to your NetBSD/FreeBSD system. I seriuosly doubt that you will be able to read the compressed DOS file system anytime in the forseeable future. 6.4 NFS/PC-NFS support The problems normally associated with PC-NFS are also associated with NFS in general. 6.4.1 Can I use 8K packets for NFS? When I try, I have all kinds of problems. In addition to the NE2000 card, this problem can also manifest itself on other ISA networks cards that have a limited amount of memory. Ken Raeburn (raeburn@cambridge.cygnus.com) has identified a common problem with the NE2000 card and provided us with a work around: -------------------------------------------------------------------- I reported previously that I was seeing problems reading files over NFS using the ne2000 driver; timeouts would eventually be reported, no data would be read. Listing files and directories (small ones anyway) were not a problem. After playing with etherfind and kernel printfs, I've come to this conclusion: Fragmented 8K UDP packets from the NFS server are not reaching the UDP layer in 386bsd. The Sun is sending them (according to another Sun spying on the network), but the UDP input routine is never called. I don't know if the bug here is on the 386bsd or Sun side, and won't have time to look into it in the next couple of days. In the meantime, mounting NFS file systems with "rsize=1024" does get rid of this problem. Ken -------------------------------------------------------------------- As a matter of policy, specifying "rsize=1024,wsize=1024" works very well also, and makes the transfers seem to run faster. This is probably because there are fewer collisions. The disadvantage of this method comes from the kernel 'sync'ing after all NFS writes. This can slow NFS accesses considerably. As with most generalizations, this one too can do nearly as much harm as good. Charles Hannum reports that he has no trouble using the default 8K packet size. If you have trouble, reduce your default packet size until the problem goes away. WIth the newer drivers (especially the ed driver) most of these problems are solved automagically. If you are still using the original 386bsd 0.1 release, you REALLY need to upgrade. 6.4.2 How do I get around the NFS "Permission denied" error? The problem is not the configuration of the server (unless there is no real requirement to run it in "secure" mode, and you happen to be running it that way anyway). The problem is the fact that, even though mount request are sent on a privileged port, NFS connections are not. This is part of secure NFS, and is not supported in 386BSD. 6.4.3 What does the message "BAD MNT RPC: RPC Authentication error; why = Invalid client credential" mean when I try to mount something from another machine? Hellmuth Michaelis (hm@hcshh.hcs.de) offers the solution to this relatively common problem: You have to make sure that the user "root" is not present in more than 8 entries in the "/etc/group" - file on the 386BSD machine. Simply remove some entries and the NFS mounts will succeed. The problem is also explained in the Clarkson Driver documentation. On 386bsd, the maximum number of groups that can be associated with a particular user is specified in the source (in a #DEFINE). In 386bsd, this number is set to 8. So, you actually have two routes you can take to correct this problem. The first is outlined by Hellmuth, above, and the second is to edit and recompile the NSF software to allow more groups. 6.4.4 What does the message "Bad MNT RPC: RPC: Authentication error; why = Client credential too weak" mean when I try to mount something from another machine? This problem is a standard NFS problem; it simply means that your user number is not one of the ones that can mount this NFS. Normally, you will get this message when you are trying to mount a filesystem from a machine that allows 'root' to mount an NFS, but limits other users. 6.4.5 I get a lot of 'ring buffer overflow' messages using NFS and the ed0 driver. Is there a problem? David Greenman (davidg@implode.rain.com), the original author of the ed0 driver, provides us with some insight into the inner workings of the ed0 driver. It always surpises me that people don't just ask the original author these questions. :-) Anyway, the reason these are happening is that the access to the 8bit boards shared memory simply isn't fast enough to deal with full wire speeds...but the driver tries hard...so even though packets get dropped, your performance only drops to about what the ethernet board is capable of (should be in the 400-600k range with an 8bit card). NFS is especially bad because the UDP window is quite large (40k last time I looked), so the overflow condition can happen easily. I've explained this for the most part in the release notes for the driver, but these didn't make it into either the FreeBSD or NetBSD releases (we couldn't find an appropriate place to put them). >From the release notes: receive ------- The 8390 implements a shared memory ring-buffer to store incoming packets. The 8bit boards (3c503, and 8003) usually have only 8k bytes of shared memory. This is only enough room for about 4 full size (1500 byte) packets. This can sometimes be a problem, especially on the original WD8003E and 3c503. This is because these boards' shared memory access speed is also quite slow compared to newer boards - typically only about 1MB/second. The additional overhead of this slow memory access, and the fact that there is only room for 4 full-sized packets means that the ring-buffer will occassionally overflow. When this happens, the board must be reset to avoid a lockup problem in early revision 8390's. Resetting the board will cause all of the data in the ring-buffer to be lost - requiring it to be re-transmitted/received...slowing things even further. Because of these problems, maximum throughput on boards of this type is only about 400-600k per second. The 16bit boards (8013 series), however, have 16k of memory as well as much faster memory access speed. Typical memory access speed on these boards is about 4MB/second. These boards generally have no problems keeping up with full ethernet speed. The only problem I've seen with these boards is related to the (slow) performance of 386BSD's malloc code when additional mbufs must be added to the pool. This can sometimes increase the total time to remove a packet enough for a ring-buffer overflow to occur. 6.4.6 Is there any PC software that will allow me to use my enormous PC with all of the unsupported hardware as a PC-NFS server? Yes. It is called SOSS, and is available from MANY FTP sources. You will need the aforementioned Clarkson Packet Drivers for it to work, but that should cause too many problems for most people. -- TSgt Dave Burgess | Dave Burgess NCOIC, USSTRATCOM/J6844 | *BSD FAQ Maintainer Offutt AFB, NE | Burgess@cynjut.infonet.net or ...@s069.infonet...