mbl900@csc2.anu.edu.au (Mathew BM LIM) (04/27/91)
Thanks to everyone who responded to my request for information on connecting MO Drives onto Suns. Several people requested that I summarise this information to the net, well here it is : ===================== My original posting ========================== >We are looking to purchase one or two Sony eraseble Magneto - Optical disk >drives for our Sun workstations. > >Has anyone any experiences with connecting a (SCSI) Sony M/O drive to a >SparcStation IPC running SunOS 4.1.1? Is the statement that "support is >built into SunOS 4.1.1 +" correct? And wil I be able to format and mount >the drive as if it were a ufs file system? Will I be able to export it via >NFS? =================== jwalz@rsg1.er.usgs.gov (Janet Walz) There are a couple different vendors' versions of such drives attached to 4.0.3 systems around here. Each vendor supplies a couple additional kernel modules and format utility (either specific to the drive, or a generic format replacement). The details are different for each vendor, and portability between vendors' formats is problematical (thus far, A's disks can be read by B, but not vice versa). If you don't have to interchange disks with anyone else, just make sure you buy all the same kind :-). Once the appropriate things are installed, formatting and mounting the optical disks looks just like other disks. I don't recall trying to export the filesystem, but it should work -- it's the host kernel's job to make it look like a normal filesystem to everything including NFS, and it certainly looks like a normal filesystem locally. They seem to work fine, but be aware that writing to them is much slower than reading, which isn't much worse than a regular disk. 4.1 has native support for CD-rom disks, but not optical ones unless they've been magically folded in as generic SCSI disks without mentioning it. ============= p554mve@mpirbn.mpifr-bonn.mpg.de (Michael van Elst) We have these drives on our Sun-3 systems. There are no problems with SunOS except that you cannot format the media. Nevertheless, the media comes preformatted so the only thing you loose is the ability to reassign bad blocks. I'm using a PC/AT to format the media (I wrote a program for the ST01 controller). To use the drive you have to label the disk with the format program. Then you can create a filesystem and mount the disk. Since the SunOS driver doesn't recognize removable media (at least with SunOS4.03) you may get a "UNIT attention" condition whenever you change the media. You can clear that condition by reading from the raw device with 'dd'. ====================== Philippe Dax <dax@inf.enst.fr> We have 2 SMO (Sony Mageto Optical) disks connected to a Sun SS1+. We use sd interface directly without others drivers, but a patch is necessary in the kernel to fix the bug about amovible disks (see BUG in sd(4)). Robert Ehlrich from Inria in France has suppleid me this patch (see below). | From ehrlich@margaux.inria.fr Wed Apr 17 20:10:02 1991 | To: dax@inf.enst.fr | Subject: Re: Patch scsi sun4 | | <<< = user | >>> = adb | ### = comments | | <<<adb -w /vmunix | <<<sd_findslave+0x178,10?ia ### maybe try more | >>>_sd_findslave+0x178: call _makecom_g0 ### or less | >>>_sd_findslave+0x17c: mov %i4, %o0 | >>>_sd_findslave+0x180: ld [%i0 + 0x10], %l3 | >>>_sd_findslave+0x184: ldub [%l3 + 0x1], %l3 | >>>_sd_findslave+0x188: srl %l3, 0x7, %l3 | >>>_sd_findslave+0x18c: orcc %g0, %l3, %g0 | >>>_sd_findslave+0x190: bne _sd_findslave + 0x1b4 ### patch here | >>>_sd_findslave+0x194: mov %i1, %o3 | >>>_sd_findslave+0x198: mov %i0, %o0 | >>>_sd_findslave+0x19c: mov %i4, %o1 | >>>_sd_findslave+0x1a0: call _sd_winchester_exists | >>>_sd_findslave+0x1a4: add %fp, -0x8, %o2 | >>>_sd_findslave+0x1a8: orcc %g0, %o0, %g0 | >>>_sd_findslave+0x1ac: bne,a _sd_findslave + 0x37c | >>>_sd_findslave+0x1b0: orcc %g0, %i5, %g0 | >>>_sd_findslave+0x1b4: call _kmem_zalloc | >>>_sd_findslave+0x1b8: | <<<_sd_findslave+0x190?W 1000000 | >>>_sd_findslave+0x190: 0x12800009 = 0x1000000 | <<<?i ### to verify | >>>_sd_findslave+0x190: nop | <<<$q | | You have to reboot to take effect. | | If it works, make the same patch in /usr/sys/sun4c/OBJ/sd.o ====================== seth@netboss1.trg.saic.com (Seth A. Phillips) A while ago a vendor sold me a SMO drive for my SUN 1E (it is a SPARC in 6U format). The salesman said it would work and it didn't so I returned it and vowed to never buy from that company again (I would mention their name but they are bankrupt now). At any rate, I learned a little about SMO drives. 1) There are two types of formating done on SMO drives: Defective Sector Slipping - scans the entire media and maps out bad sectors. Linear Replacement - writes to disk only the information needed to map out bad sectors and thats it (no scanning or mapping is performed). This is what is done on the platters at the factory. 2) The SUNOS 4.0.X format program can't do the needed Defective Sector Slipping option. Thus, you end up using the platter as is, defective sectors and all. 3) I don't know if 4.1.X has solved this problem. 4) Pinnicle MicroSystems (I didn't buy from them) sells a SMO drive with their own formatting program. 5) The drive I received didn't work for other reasons as well (something about an incompatability between the 1E SCSI driver and the SMO PCB). 6) I think you can get what you are looking for somewhere, but you need to weed through greedy, dumb salesmen that will tell you anything. ================ jws@sv001.sandiego.ncr.com (James Smart) I worked on the Erasable Optical Driver sold by Artecon. The driver works on the Sony, Ricoh, and Tahiti Drives. Support for the Sony is included in SunOS to the point that if a "formatted" cartridge is inserted, and a "proper disk geometry" is known, the SunOS format, newfs, fsck, will allow the cartridge to be partitioned and filesystems created. After this, the standard "mount/umount" commands treat the cartridge as a normal disk filesystem. Once you've reached this point, there's no problems with exporting the filesystem (other than the cartridge can be removed and cause extreme headaches to those that have mounted it). NOTE: that special utilities must be created to issue a FORMAT command to the drive as the standard SunOS format command is incompatible. Defect list management is also incompatible. It also takes some effort to generate a disk geometry to properly map the contents of the cartridge. Take note that SunOS 4.1 (mkfs & fsck) had a problem handling geometries of 1 head. A patch is available from Sun for this and the patch should have been included in 4.1.1. My recommendations for the best optical drive is the MaxOptics Tahiti drive. The Tahiti has better performance, and supports an optional ZCAV cartridge format (which is similar to ZBR on standard disks) that has a capacity over 1GB. There was also a difference in formatting. The Sony would not discover as many defects during format, resulting in a larger grown defect list (and performance hits when the blocks were remapped during operation). The Tahiti found most (if not all) defects during format, and rarely grew defects. Some Distributors of Erasable Optical Drives in the States are: Pinnacle Micro Delta Micro Artecon Andataco Apex ================== haydens%bullwinkle@xn.ll.mit.edu (Hayden Schultz) We buy magneto-optical drives frim Pinnacle Microsystems. I think they may simply be a VAR for the Sony disks. They're 200 MB per side, Sony makes the media that we use. It works just like a regular unix filesystem. NFS works too. ================== reed@hammer.whoi.edu (Reed) While I cannot comment on your exact configuration, I can give you this information. I have a sony MO (packaged by a company called Pinnacle, as the REO-650). While I had a bear of a time getting it to work on my 3/160, when I moved it to a SS1+ under 4.1, the install was a breeze. As to m ounting it, here's the line, right out of my /etc/fstab /dev/reo0g /usr/export/home/hammer1/reed/reo 4.2 rw 0 0 manual "mount" and "umount" also works. I have exported this disk to my local net, and others (on SS1's, ss2's, and IPC's ) have been able to mount it/ read it w/o a hitch. I also have used other suppliers of this drive, and again, w/o major difficulty. Hope that helps, ========================= reed@hammer.whoi.edu (Reed) ( in response to my further query about wether he could read / write disks formatted on drives from different vendors) No. As yet, noone seems to have agreed on how to format the disks, so they all do it differently. I do plan to experiment some this summer with ignoring their instructions and attempting to find a least common denominator, but I doubt that will be in time to be of assistance to you. Unless for some reason you are stuck on the sony's I would reccommend looking into the Maxor Tahiti drive. I believe it has been packaged by a group called MAXIMUM Storage, and they call it hte Duette, system 7. Best part about this, other than speed, compatibility, and size (1 Gb, as opposed to the paltry 250 Mb you can get per side on a Sony after formatting), is the fact that it doubles as a WORM drive. If I didn't already have the pinnacle, I'd look into one of these seriously. If you want more info, their particulars are below. ++++++++++++++++++++++++++ SUMMARY +++++++++++++++++++++++++ 1) there are two basic types of drives, ISO standard (eg : Sony) drives with a capacity of ~350MBytes / side and a newer Maxtor Tahiti drive with a capacity of ~1GByte (and doubles as a WORM drive) 2) Most vendors require / supply a format program for the drive. After formatting, the disks may be treated exacatlly as a winchester drive (can use mount, umount, newfs, etc.) 3) In general, disk formats are vendor dependant, so you cannot interchange disks. 4) SunOS4.0.3 does not support removable media, but there is a patch. 5) The SunOS format program does not support Defective Sector Slipping, needed by MO drives. 6) Recommended drive - MaxOptics Tahiti My thanks to all those who responded. Mathew Lim, | Telephone : +61 6 249 2750 Unix Systems Programmer, | Fax : +61 6 247 3425 ANU Supercomputer Facility, |