Floppy Drives

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Yes, really. I’ve got hundreds of the damn things here at home, and I
want to go through them and get rid of them all.

But… to do that I want to read them. I have both a 5.25″ and a 3.5″
drive, both are plugged in, but in the BIOS, all I see is the 3.5″. Fine, I figure I’ll take care of those.

Nope. I see /dev/fd0 once I’ve booted up, but neither konqueror nor mount nor fdisk works – the latter telling me that /dev/fd0 is not a valid block device. After some googling, I tried modprobe floppy, which installed it, but still no joy.

Anyone have a clue?


47 thoughts on - Floppy Drives

  • What file system is on them? Or did you do something like raw tar writes to them? If it is typical dos/window FAT, try the programs from the mtools package. mdir, mcopy, etc. I hate to fight with stuff like that so I’d probably use a windows box connected to a samba share to move things over.

  • All of ’em are old DOS. Just tried mdir a:, and the same: can’t open, can’t initials A:. I really doubt the drives themselves are dead, but….


  • Floppy disks have a finite usable life. Depending on where and how you have been storing them, they may be shot.

  • Yeah, but…. I tried three of ’em, three different OEM, and three ages, and they all give me fdisk saying it’s not a valid block device.

    Is it possibly that there’s some driver missing?


  • If they were all written with the same drive it’s also possible the head alignment had drifted which will make things…interesting.

    Try formatting a scratch floppy to see if you can write. If that works but you still can’t read, evidence that it’s indeed an alignment mismatch.

  • These are many years of disks, written on many machines.

    At any rate, I just tried mformat a:, and it tells me that it can’t open
    /dev/fd0: No such device or address.


  • It’s been years since I used floppies on a linux system; but when I still hada 3.5 inch drive, I recall that I first had to put a floppy in, then do a mount command.

    I realize that the contributors on this thread, as well as the originator, may take this is a given, but in the event this hasn’t been done, and it’s a way to get the disk readable (I haven’t seen it mentioned yet as possible solution).

    My two cents,


  • lrwxrwxrwx 1 root root 13 Apr 7 15:03 /dev/fd -> /proc/self/fd/

    And, while we’re at it, ll of /dev/floppy shows

    lrwxrwxrwx 1 root root 3 Apr 7 15:03 /dev/floppy -> fd0


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  • Interesting as that doesn’t match the pattern /dev/fd?

    fd0 should have been shown by the ls -l /dev/fd? pattern so is that a broken link?

    “lsmod | grep floppy” – does it show the floppy module loaded?

    If “ls -l /dev/fd0*” does not show a series of device nodes try:

    “/sbin/MAKEDEV fd0”

    and retry the operations that are failing.

    If this still fails ensure that the device is enabled in the system’s bios. Speaking of that, is the device seen at boot time?

    “dmesg | grep ^Floppy” or “grep ^Floppy /var/log/dmesg” should show fd0
    and a size.


  • Note that /dev/fd has nothing to do with floppy drives. /dev/fd deals with file descriptors, not floppy drives.

    Just to avoid confusion.

  • Ok, ll /dev/fd – which is a directory – shows it pointing to
    /proc/self/fd/. Under tghat is 0-3, where 0-2 are links to /dev/pts/0,
    *all* the same. 3 is a link to /proc/5038/fd/, which does not exist.

    Is it time to try MAKEDEV?


  • Perhaps you didn’t understand what I wrote in the paragraph that you cut out.
    >> If “ls -l /dev/fd0*” does not show a series of device nodes try:

    It does – /dev/fd0, along with all 14 sizes of floppies, of a patter

    Now, if that’s not clear enough for you, let me rephrase: /dev/fd0
    exists, as does the related ones, as far as I know (note that ll for me is aliased to “ls -laF”).

    brw-rw—- 1 mark floppy 2, 0 Apr 7 15:03 /dev/fd0
    brw-rw—- 1 mark floppy 2, 84 Apr 7 15:03 /dev/fd0u1040
    brw-rw—- 1 mark floppy 2, 88 Apr 7 15:03 /dev/fd0u1120
    brw-rw—- 1 mark floppy 2, 28 Apr 7 15:03 /dev/fd0u1440
    brw-rw—- 1 mark floppy 2, 44 Apr 7 15:03 /dev/fd0u1680
    brw-rw—- 1 mark floppy 2, 60 Apr 7 15:03 /dev/fd0u1722
    brw-rw—- 1 mark floppy 2, 76 Apr 7 15:03 /dev/fd0u1743
    brw-rw—- 1 mark floppy 2, 96 Apr 7 15:03 /dev/fd0u1760
    brw-rw—- 1 mark floppy 2, 116 Apr 7 15:03 /dev/fd0u1840
    brw-rw—- 1 mark floppy 2, 100 Apr 7 15:03 /dev/fd0u1920
    brw-rw—- 1 mark floppy 2, 12 Apr 7 15:03 /dev/fd0u360
    brw-rw—- 1 mark floppy 2, 16 Apr 7 15:03 /dev/fd0u720
    brw-rw—- 1 mark floppy 2, 120 Apr 7 15:03 /dev/fd0u800
    brw-rw—- 1 mark floppy 2, 52 Apr 7 15:03 /dev/fd0u820
    brw-rw—- 1 mark floppy 2, 68 Apr 7 15:03 /dev/fd0u830

    Is that clear enough?


  • Mark, you said that both floppy drives are connected. Could it be that both are wired to fd0? One drive could be malfunctioning…. Try with only one drive connected at a time at the end of the cable and see if that helps… Louis

  • I saw in an earlier part of the thread, you were trying to do things to A: … A: is a windows device, not a Linux device

    Make sure you are trying to do things to /dev/fd0 and not A:

  • To debug this, I’d do the following:

    1. Remove both USB plugs (I assume that these floppies are USB connected)
    2. Reboot
    3. Plug just one in, then do
    lsusb and get the end of /var/log/messages One of these might tell you where the floppy is connected in /dev. It might not be /dev/fd0
    4. If it doesn’t show up immediately, try putting in a floppy disk and do 3
    5. If it doesn’t show up again, then it’s probably dead.
    6. If it does show, perhaps at /dev/sdb1, then create a file .mtoolsrc:
    # USB drive
    drive u: file=”/dev/sdb1″
    Then do
    mdir u:

    Of course, it will probably show up at /dev/fd.

    Just my pre-tax 2 cents.

  • Johnny Hughes wrote:

    Oh, of course. I was trying mdir, I think – that’s an mtools thing – they use a: internally to represent /dev/fd0.


  • That was in the context of the ‘mtools’ programs – which do map the devices to dos-like letters but failed in the same way with a problem with the underlying device. But as someone else mentioned, if 2
    drives are plugged in, it may be trying the wrong device.

  • Hi, Louis,

    Louis Lagendijk wrote:

    Good thought… but I think I had one of them disconnected before I took my system down yesterday and connected both. I will note that the 5.25″
    one’s light does seem to stay on, regardless.

    I was speaking about it to my manager this morning, and he pulls out a
    3.5″ USB drive I can borrow, so I’ll take my system down, pull the 3.5″, and see what I see.


  • mark writes:

    Floppy drives also have a limited lifetime. Are you sure the drive itself
    (not the disk) is good?

    I also have a bunch of old floppies and try to keep at least one system with a working floppy drive. I see:

    [dave@waste ~]# ls /dev/fd*
    /dev/fd@ /dev/fd0u1120 /dev/fd0u1722 /dev/fd0u1840 /dev/fd0u720
    /dev/fd0 /dev/fd0u1440 /dev/fd0u1743 /dev/fd0u1920 /dev/fd0u800
    /dev/fd0u1040 /dev/fd0u1680 /dev/fd0u1760 /dev/fd0u360 /dev/fd0u820
    [dave@waste ~]# ls -l /dev/floppy lrwxrwxrwx 1 root root 3 Apr 3 17:17 /dev/floppy -> fd0
    [dave@waste ~]# lsmod | grep floppy floppy 57125 0

    on that system and it reads and writes floppies.

    Cheers, Dave

  • Max Pyziur wrote:

    *shrug* In houses, apts, where I live, not in storage (except possibly for a couple months, and that was all climate-controlled storage).

    That I don’t know, and was trying to think of a way to test it. As I noted in another post, the 5.25″ light seems to stay on, and I *think* that was the one I had disconnected before. I also think I mentioned that after bringing it down, connecting, and rebooting, I looked at the BIOS, and it told me it *only* saw the 3.5″ drive.

    a) Not at home. b) Not really relevant, since I don’t have a floppy entry in it, just my h/d partitions.

    It *looks* like udev knows about it, since it created /dev/fd0 and the related devices.

    Btw, I updated before I brought it down, so it’s on current 5.9.


  • if I remember correctly, PC floppies require a cable with a twisted bit in it. both drives are jumpered for disk1, and the flip makes the end drive disk0 if you used a straight through ribbon cable and both drives were jumpered for the default, then they would have collided and not worked.

    its been 10 years since I’ve hooked one up, so this is from old memories.

  • OH. another rusty old memory. if you plugged a floppy cable in upside down (only possible if the cable wasn’t keyed, but I remember quite a few that werent), it grounded both drive select and write select, and the drive would write nulls (or something) all over any track that was seeked to, without even sector formatting. this would, of course, erase any disk you inserted. also, the LED would stay on.

  • That is why I thought of the cable/drive issue. Please keep in mind that the bios versions I recall did not detect a drive unless it was told that there was one (you had to even specify the type/ format of the drive)
    the bios. Look around in the bios and check if you can specify the format of the floppy drives somewhere… And the comment about checking if the cable has been put on upside down
    (on either side). Please note tat the twist in the cable sits between drive a and b. Still 4 possibilities to try.


  • John R Pierce wrote:

    I *think* these cables are keyed – they’re “relatively” new, but I’ll check. I still think I had the 5.25 power on, but not the cable…. Something to check this evening.

  • Louis Lagendijk wrote:

    OH! I thought, since the m/b is from ’05 or ’06, that it would detect the floppy drives, but *that* I need to look at. Thanks!


  • the floppy interface was really low level. all parallel signals, like select drive, step, direction, head select, serial data, clock, write enable, and a status line for home, and index (the hole in the disk that said its at sector 0).

    the ONLY way to detect a drive is connected was to STEP outwards 100
    times, checking for the ‘home’ status each time, this takes several seconds per drive. AFAIK, there was no way electrically to tell the difference between drive types, unless there’s a reliable disk in the drive. so the BIOS’s pretty much stopped doing the auto-home-and-detect thing early on when floppies became optional because it was /so/ slow and added significant time to POST. and even from the very beginning, you have to configure the BIOS for the drive types (heck, early hard disks had to be configured in the BIOS too)

  • John R Pierce wrote:

    But post, if memory check is enabled, *does* take a long time… oh, that’s right, that was on the server with ->256G< -.... mark “and my mind SEGV’s whenever I say that”

  • Dale Dellutri wrote:

    Wrong assumption. They’re on the FD cable to the m/b. I’ve got some *old*

    I’ll tell my wife, who’s working on the taxes, to include that as income….


  • Separately, on some Ubuntu boards there has been discussion about a program called udisks for disk-related issues. It is available for CentOS
    6, not for CentOS 5. Where “mount” commands have failed, udisks for these Ubuntu users has come through.

    Ironically, this discussion got me interested in whether or not the floppy drive on a home server running CentOS 5 is accessible via CentOS5. It isn’t; no heartbreak, just a mild annoyance.

    Max Pyziur pyz@brama.com

  • You gents nailed it. I brought my machine down again, and set the BIOS
    to see the 1.2M as a, and the 1.44 as b: while it was down, before I did that, I looked… I’m sure the cable was on, but it’s really hard to see the open side of the case still covers about a third of the board, and with all the cables…. Pulling out my trusty minimag, and moving cables… and it was upside down. I don’t know how it got on that way, certainly I wouldn’t have forced it, but flipped it over, and played with the BIOS… the 3.5″ drive still doesn’t work… but the 1.2M
    floppy, as b: *does* work – light goes on only when I try to read it, and not otherwise.

    Now I don’t know if I have a drive cleaner, since I can’t believe none of the first 10 or so disks I tried to look at was readable.

    But I’m over the first hump. Now I’m playing with /dev/fd1 and
    /dev/floppy-fd1 (and why is it trying to read a superblock when I try to mount it, when I’ve said -t msdos? Oh, well, onward in the fight.)


  • mark writes:

    I think mount uses the same error string (possibly from ERRNO) whenever it can’t find the appropriate file system structure on a device. Thus, you get
    “Unable to read superblock” even when mount -t msdos is looking for a FAT
    and FAT root directory.

    Cheers, Dave

  • David G. Miller wrote:
    a FAT

    Hmmm… didn’t see it mounted, but I’ll try more tonight. Last night included a) playing with system, and b) finishing up our federal taxes….

    mark “and getting a headache”

  • Frank Cox wrote:

    mtools is a desperation move, since I haven’t actually read anything from anything yet. As I mentioned, I *may* have an old drive head cleaner somewhere – since it’s not been used in about a decade, I’m thinking of corrosion or crud.

    I also can’t seem to find the USB 3.5″ drive I borrowed – lsusb sees it
    (at least since the last reboot), but trying to find it to mount it is something I’m still digging at, and I doubt mtools can find it.


  • As far as I remember (I’m not as young as I used to be, and it’s been a while), the 3.5″ USB floppy drive here would recognize a (formatted)
    floppy when inserted and mount it automatically, on CentOS 5.x.
    (assuming it contained a recognizable filesystem…)

    now that I”m running 6.4, I haven’t tried the floppy drive yet.

    (I have piles and stacks and drawers of 5.25 and 3.5 inch floppies with various stuff stored on ’em. I used that usb drive (and an internal 5.25
    inch drive) to grab images of all of them (with dd) which I’ll eventually organize and burn onto CD or DVD, so I can get rid of all the floppies.)


  • Fred Smith wrote:

    Even if there’s nothing about floppies in /etc/fstab? Or is that something I need to configure for autofs?

    Exactly my goal right now.


  • As far as I can remember, yes.

    I’ll try it on the 6.4 system that’s now running on that box and see what happens.

  • Just to obtain some empirical data I have connected a usb 3.5 FDD unit to my CentOS-6.4 workstation and inserted a previously unused 3.5
    HDFD. The Nautilus system automatically opened a window on my desktop and I was able to copy and removed files from the diskette without any difficulty.

    A peek into /media shows this:

    # tree /media
    └── disk

    1 directory, 0 files

    While /etc/fstab shows me nothing that obviously relates to the fdd:

    # cat /etc/fstab

    # /etc/fstab
    # Created by anaconda on Mon Sep 24 12:57:28 2012
    # Accessible filesystems, by reference, are maintained under ‘/dev/disk’
    # See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
    /dev/mapper/vg_vhost04-lv_root / ext4
    defaults 1 1

  • Note: the USB floppy may be showing up as /dev/sd[bcd…n]
    At least that is what happened when I used one on RHEL/CentOS5 a while back.

    I suggest unplugging the USB floppy, execute `ls /dev/sd* /dev/fd*`, plug it in and execute `ls /dev/sd* /dev/fd*`, and then note the differences.

    {there are probably hal/udev/inotify games you could do, but I like old fashioned things.}

    Even when this disclaimer is not here:
    I am not a contracting officer. I do not have authority to make or modify the terms of any contract.

  • Denniston, Todd A CIV NAVSURFWARCENDIV Crane wrote:

    I would think, but don’t remember seeing it.

    Think I tried that, as well as leaving the USB drive in when I bounced the system to reset the BIOS. USB storage annoys me, half the time it’s try to find it, the camera card being a prime example. I’ll try it this evening, since we *finally* finished all the taxes last night (MD is nasty: their downloadable pdf forms are encrypted, so not only is it not saveable after you enter data, like the fed forms are, but you cannot use either print to CUPS-pdf, nor can you print to a file, then use ps2pdf….)

    Hmmm, don’t know them. rescan-scsi-bus… no, I don’t *think* that will register the USB, and I think I mentioned that lsusb shows me the drive, but I can’t identify the driver. Now that I have some time, I’ll dig deeper.

    I have a very long disclaimer from my late wife at home, along the lines of “this does not reflect the views of my employer, the US government, or even the view out my window (which I don’t have)….”