Remount an ejected USB Stick?

[sambul13]

Is there a way to remount an ejected but not detached USB Stick without reinserting it into a Plug? Once ejected, it reads in dmesg as /dev/sdb, without any volume IDs.

[pepedog]

Lazy way if auto mount, install parted and run partprobe
Or use mount
Or have an fstab entry and run mount -a

[sambul13]

Thanks, but it doesn't work, because once the Thumb is ejected, it doesn't show any volumes in the system, only appears as /dev/sdb. I.e., there is no /dev/sdb1 that I can mount by known means. The volume needs to be found, or device rescanned, or its info refreshed 1st - any ideas?

[karog]

Here is a wild guess that finds SATA on Pogo V3's and who knows might work. Worth a try
$this->bbcode_second_pass_code('', '
echo "0 0 0" > /sys/class/scsi_host/host0/scan')
where
$this->bbcode_second_pass_code('', '
echo "c t l" > /sys/class/scsi_host/hosth/scan
')
In the previous command, last h in hosth is the HBA number, c is the channel on the HBA, t is the SCSI target ID, and l is the LUN.

[sambul13]

Unfortunately, the wild guess doesn't work. Here is what I got once the Thumb was originally mounted and then ejected:

$this->bbcode_second_pass_code('', 'sdb: sdb1
------------------------------------------------------
sd 8:0:0:0 [sdb] Attached SCSI removable disk # mounted
------------------------------------------------------
sdb: detected capacity change from 4049600512 to 0 # ejected

echo "0 0 0" > /sys/class/scsi_host/host8/scan # no change in dmesg')

I wonder if playing with udevadm trigger & settle can do the trick? Tried so far with no luck. See What happens when a USB drive is plugged in?

[sambul13]

$this->bbcode_second_pass_quote('karog', 'e')cho "0 0 0" > /sys/class/scsi_host/host0/scan

[hydro]

I think this is some kind of bug in eject or xfce. It won't remove device nodes of motorized drives
$this->bbcode_second_pass_code('', '
# mount /dev/sdc1 /mnt
# mount|grep mnt
/dev/sdc1 on /mnt type fuseblk (rw,nosuid,nodev,relatime,user_id=0,group_id=0,allow_other,blksize=4096)
# eject /dev/sdc1
# mount|grep mnt
# ls -1 /dev/sdc*
/dev/sdc
/dev/sdc1
/dev/sdc2
/dev/sdc3
')
I don't know why non motorized media device nodes are removed (this one has one partition only):
$this->bbcode_second_pass_code('', '
# mount /dev/sdb1 /mnt
# mount|grep mnt
/dev/sdb1 on /mnt type fuseblk (rw,nosuid,nodev,relatime,user_id=0,group_id=0,allow_other,blksize=4096)
# eject /dev/sdb1
# ls -1 /dev/sdb*
/dev/sdb
')
But it can be recreated
$this->bbcode_second_pass_code('', '
# eject -t /dev/sdb
# ls -1 /dev/sdb*
/dev/sdb
/dev/sdb1
# mount /dev/sdb1 /mnt
# mount|grep mnt
/dev/sdb1 on /mnt type fuseblk (rw,nosuid,nodev,relatime,user_id=0,group_id=0,allow_other,blksize=4096)
')
This does not work with every usb stick. So in my opinion the question is not how to rescan the device but why eject removes device nodes or rather why does xfce not just do a simple unmount.

Edit: You should link related threads
viewtopic.php?f=6&t=4002&p=22618
https://bbs.archlinux.org/viewtopic.php?id=151086

Edit2: Seems like the xfce devs expect you to not unmount/eject a removable device unless you intend to physically remove it afterwards.
http://comments.gmane.org/gmane.comp.de ... devel/4081

[sambul13]

Yah, it looks like Eject command includes USB Sticks improperly instead of Remove.

There may be indeed cleaner solution - avoid using relevant Thunar Volume Manager features in XFCE, since they seems to duplicate basic OS features.