How to detect USB devices plugged in

[joneall]

The automatic notifier, which signals when for instance a new USB disk has been plugged in, works very erratically for me. In particular, it does not detect CDs entered into my external USB CD drive. There is no USB device symbol shown on the system tray. Is there a way to mount a CD in a device manually, without waiting for the notifier? In which case, how do I know which device is the CD drive, with a name like /dev/sr0?

I have tried it with VLC, but either I chose the wrong drive (/dev/sr0) or something else does not work.

Alternatively, is there a way to "fix" the automatic notifier?

[Fred47]

A quick search brought up several sites showing the commands. For example https://linuxconfig.org/howto-mount-usb-drive-in-linux

[joneall]

I missed that one because I thought it was only talking about the mount command and my problem preceded the use of that.

THanks.

[joneall]

Problem is, fdisk -l gives a long list of stuff and it's impossible for me to know what is what. There are a lot of entries like

Disk /dev/loop6: 66.56 MiB, 69795840 bytes, 136320 sectors

which I do not understand at all. All I see different in lsusb is the following entry:

Bus 005 Device 003: ID 13fd:1040 Initio Corporation INIC-1511L PATA Bridge

I'm trying to use an external USB CD reader, which works just fine on my wife's WIndows 10 machine. Needless to say, I have no Windows system on my computer.

I do have an internal CD/DVD reader. When I put a CD in there, the drive makes some noises, but Kubuntu remains silent without apparently detecting anything. Very annoying.

[Schwarzer Kater]

Did you try if you get more information with e.g. lsblk -e7 -f? (the -e7 suppresses snapd's loop devices)

Hm, when I insert an audio CD in my internal drive a message pops up in Plasma and I can see it in the system tray…
The CD is also shown in the "removable devices" section in Dolphin…
Unfortunately I don't have an external USB CD/DVD player to test this.

What kind of CD are you trying to access?

[Snowhog]

Disk /dev/loop6: 66.56 MiB, 69795840 bytes, 136320 sectors

Those are all SNAP application mounts. SNAP does a crappy job of cleaning up its mounts!

[joneall]

Actually, I have an internal CD drive and that is not detected either. Seems to be a CD reader problem, whatever that can mean.

[joneall]

Did you try if you get more information with e.g. lsblk -e7 -f? (the -e7 suppresses snapd's loop devices)

Hm, when I insert an audio CD in my internal drive a message pops up in Plasma and I can see it in the system tray…
The CD is also shown in the "removable devices" section in Dolphin…
Unfortunately I don't have an external USB CD/DVD player to test this.

What kind of CD are you trying to access?

I used to get the popup message too, but not for months now. The CD in question is an ordinary audio CD. It ought to work for DVDs too, tho.

[oshunluvr]

For what it's worth, I have a Blu-Ray CD/RW drive in an external enclosure attached to my desktop PC via USB 3.0. Inserting a disc results is the expected notification and pop-up message and it appears in Dolphin.

Frankly, it sounds like a hardware issue OR some past upgrade bug is the problem..

[oshunluvr]

I wonder if a Live USB session would show different results.

[joneall]

I wonder if a Live USB session would show different results.

Good idea, thanks! I tried it, but the result is the same. None of the three systems detects an internal PCI or an external USB CD/DVD reader. All three detect external USB disk drives. I don't understand how it could be hardware, in that case. Any more thoughts?

[Schwarzer Kater]

[…] None of the three systems detects an internal PCI or an external USB CD/DVD reader. […]

The internal CD/DVD drive is probably connected to SATA if it is a more or less modern computer.
Any chance to quickly swap it for another internal one to test if the spare one works?

Has the internal CD/DVD drive ever worked or is it a brand new machine and you are testing this for the first time? Specifications of the computer could be helpful in that case, too.

[oshunluvr]

Well the next thing I would do is install and boot to an older kernel. You said "several months" since you got the pop-up so go back that far. This will probably require some research to figure out what version to install. You could also just move back a series, like if you're using 5.19 go back to 5.15. It almost sounds like a module is missing so UDEV can't do it's job.

Also I looked back at your first post and one question was left unanswered: If you have more than one CD-ROM drive they would be /dev/sr0, /dev/sr1. etc. I suspect that issuing an eject command would reveal which is sr0.

/usr/bin/eject -T

[joneall]

Thanks for all the suggestions. The eject command works fine for the internal CD/DVD drive. I only have one in ternal drive, which is /dev/sr0, as shown by eject -T /dev/sr0. It knows the drive is there, but does not detect when there is a CD in it.

When I plug in the external USB drive, I hear a buzz in my speakers. The eject command works on that drive too (/dev/sr1).

I can put a CD in the external drive, then open disc /dev/sr1 with VLC and I get the music. I can also watch a movie on a DVD on the external drive by picking that disc with VLC. It doesn't work with the internal drive tho.

I don't see how it can be only hardware. Maybe the internal drive has a h/w pb, tho.

Thing is, when I insert a medium, I never get a message from the prompter. Is there some software module which manages that and which I can remove and then re-install? Or reconfigure.

[Schwarzer Kater]

[…] Is there some software module which manages that and which I can remove and then re-install? Or reconfigure.

The only thing I can think of in the GUI is -> System Settings -> Hardware -> Removable Storage -> Device Actions …
Perhaps also -> System Settings -> Personalization -> Applications -> File Associations.

Or it is some corrupt cache or settings file in your $HOME…

But I am just guessing now.