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waddles 02-26-2013 11:41 PM

Addressing flash drive
 
I have su set up in a separate window and run root commands from there. fdisk -l still showing only the hd: sda & sdb.
This time the fdisk command did not cause rapid on/off of lamp and the on/off cycle remained at 1 sec.

TobiSGD 02-26-2013 11:52 PM

Do you get any error messages when running
Code:

fdisk /dev/sdc
or when you try to mount the partition sdc1?

waddles 02-27-2013 12:30 AM

Addressing flash drive
 
fdisk /dev/sdc yields:
fdisk: unable to open /dev/sdc: Resource temporarily unavailable

Haven't tried to mount sdc1. Will give it a shot.

waddles 02-27-2013 01:02 AM

Addressing flash drive
 
Here is what I get for trying to mount it:
mount -t vfat /dev/sdc1 /mnt
mount: special device /dev/sdc1 does not exist

Shadow_7 02-27-2013 03:19 AM

$ cat /proc/partitions

If it doesn't show up there, then there isn't much you can do. Until it does show up there by loading a module or other means. I ran into a similar issue when I tried to run IceWM on ubuntu a few years back. Switching back to what was gnome at the time and ubuntu's default wm, made it work again. Oddly I've never had an issue like that on any other distro. Although I have had to modprobe usb-storage manually before. And other scsi modules in those early days. Which didn't seem to work in ubuntu's case at that time.

waddles 02-27-2013 05:05 AM

I took another look into /proc and found when I plug in the flash drive that nothing occurs in partitions but that in scsi a directory is created called usb-storage which contains a file identified by a number. This and shadow 7's note leads me to think that Slackware 13.37 may have its own peculiarities. I will search /proc to see if I can dig up anything.

In the meantime can anyone explain why lsusb recognizes the flash drive but after a few minutes it no longer does?

Later...
I unplugged and plugged the flash drive back in and scampered over to /proc/scsi and waited for the usb-storage directory to form. I then cat-ed the numeric directory and got:
cat 17
Host scsi17: usb-storage
Vendor: SanDisk
Product: Cruzer
Serial Number: 20060775120CCBC0F3E6
Protocol: Transparent SCSI
Transport: Bulk
Quirks: SANE_SENSE
After 2 min +/- the file & directory goes away but the drives lamp continues to blink at 1 sec. intervals.
Too sleepy to continue this tonight will fiddle in the am.

waddles 02-27-2013 03:39 PM

Addressing flash drive
 
For Slackware 13.37 here is what I have found in /proc for the flash drive:
Code:

# cat /proc/scsi/scsi
Host: scsi11 Channel: 00 Id: 00 Lun: 00
  Vendor: SanDisk  Model: Cruzer      Rev: 1.26
  Type:  Direct-Access                ANSI  SCSI revision: 02

# ls /proc/scsi/usb-storage
13
# cat /proc/scsi/usb-storage/13
  Host scsi13: usb-storage
        Vendor: SanDisk
      Product: Cruzer
 Serial Number: 20060775120CCBC0F3E6
      Protocol: Transparent SCSI
    Transport: Bulk
        Quirks:

# cat /proc/scsi/sg/device_strs
  ATA          WDC WD800JB-00JJ        05.0
  ATA          WDC AC22000L            32.4
  PHILIPS      DVD+-RW DVD8701        5D24
  E-IDE        CD-ROM Max 50X          6.40
  SanDisk      Cruzer                  1.26

Some of this information must be gained within about 2 minutes of connecting the flash drive or it will disappear.
I have not confirmed this but believe that the flash drive must be mounted to preserve the information longer and an entry must exist in /etc/fstab in order to mount it.
Can someone confirm this otherwise I cannot know if the device is failing or not.

TobiSGD 02-27-2013 06:50 PM

Try it with a different OS, for example a live-CD with a different kernel or a Windows install on the same machine, to make sure if this is Slackware related.
Try it on a different machine to test if the issues are related to your hardware.

waddles 03-01-2013 03:35 PM

Addressing flash drive
 
I used a SEMA SY-5EMA mobo platform with Slack 13.37 as a test bed and found:
1) Without modifying the BIOS I could immediately fdisk the San Disk and I could have partitioned had I wanted then.
2) /proc info did not disappear after a couple of minutes.
That was with the San Disk installed at bootup.

Took the San Disk back to my main platform (where I was initially) and with the Flash Drive installed during bootup I experienced a hang immediately after after it showed the devices HD, DVD, CDROM, etc attached. Pulled the San Disk and it continued-- could be anything because it did not happen again however with the flash drive attached it seemed it took a long time to get thru some of the bootup stuff.
I jumped back into the BIOS and discovered that it is necessary to disable all of the boot sequencey before it recognizes any added bootable devices like the flash drive to be used as a boot device. It is called a USB RMD-FDD which is an armed device such as an LS-120 or zip drive acting like a floppy drive. But that is the only USB option it provides for that flash drive. Now I know at least that I can boot from the flash drive.
After making the change and with the flash drive connected after booting I still am unable on this platform to fdisk the flash drive AND the flash drive info disappears from /proc locations after a couple of minutes.
Later I will try different USB ports to see if that changes things but it is looking suspiciously like a USB problem on this platform. Will examine situation with camera and printer to see if they have a problem.
---
Sorry for supposedly dual posting but was attempting to focus to the San Disk to eliminate it as the problem.

waddles 03-02-2013 06:41 PM

I have just learned from:
http://forums.sandisk.com/t5/All-San.../255218/page/2
that this drive will go read only permanently if large enough file is written to it. This SanDisk Cruzer 16GB is going back to Target for a refund. I am presuming the intermittent recognition may be related to SanDisk's problem.


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