I hooked up my Dell Precision 490 to an old decent tape drive via it's cable. But the Linux OS does not show it. If I lsscsi it just shows the CD-ROM and hard-drive.

Since I've been off this job for a while, I have forgotten some of the Linux diagnostic commands, but it's slowly coming back to me. I have NO idea why the OS does NOT see the tape drive.

Any help appreciated - I don't see a /dev/sg2 which is normally what I would see.

I also need help troubleshooting why one of my Dell Precision 490s no longer boots up, the display never displays anything and the PC beeps about 7 times. The light on is 4.

THe BIOS boot part of the sequence says something about Device, ports and it says it found 1 device. Is that the tape drive? I'll have to describe that in more detail.
So yeah, I'm not seeing /dev/sg2. There should be a /dev/sg2.

BIOS sayd Controller Bus#00, Device#1F, Function#02, 01 Ports, 01 Devices - Is this the tape drive? So the BIOS sees it? The SCSI controller detected it? Should I just put some sort of modprobe in my .profile and make sure the generic tape driver is in there on boot? Would that help? But I already see tg3 in there.

tg3 is the Broadcom ethernet module, st is the tape drive module?

Does lsmod show st being loaded?

It's not loaded but may I ask what is st? I only use generic drivers - is that generic?
Why did I mention tg3, hmm?

Should I modprobe st and then report back? It says modprobe: ERROR: could not insert 'st': Operation not permitted.

Should I modprobe sg instead? Obviously I can't modprobe st it doesn't exist I guess. But I don't need it? Or so I?
Please explain if you can. I just forget a lot because one of my machines that was super important died a while
back and i don't have my saved catted files of terminal sessions. It's really a huge disappointment that I have to start
over. Unless I can somehow get the hard drive and mount it somewhow and read the old files on it. That would be great.

Yes, st is the scsi tape drive module. What linux distribution is running on the dell?

I know what at least part of the problem is - the module st is NOT being loaded because my computer
is NOT detecting a tape drive, otherwise, it WOULD be loaded. Something is very wrong.

I can modinfo st and get that the driver is there in the /lib/modules/..../st.k0


It's there but it's not getting loaded because the tape drive is not being detected.

Did you understand my question about the BIOS?

Can I explain something? This system used to work perfectly. Can you think why it does not now, do you feel it's hardware or software - I have no idea at this point as the scsi card is detected, but that isn't really asking the scsi adapter to do much - it could be detected by unable to do it's job?

The Kernel is 4.10.0-38 or some such kernel. GNU Linux. It's Linux Mint 18.3

I wonder is BIOS says Controller Bus#00, Device#1F, Function#02, 01 Ports, 01 Devices - Is this the tape drive?

I need to explain something - I use a different generic tape driver than the one you are mentioning. I use sg not st.

I don't get /dev/stx I get /dev/sgx, specifically /dev/sg2. I even have runs saved on the computer of that device being
used in my commands to the tape drive. So I will need to look up how to load the generic driver - it's a differnt driver than st I would guess.

I wonder if some sort of terminator fell off of the tape drive? I have no idea which part needs to be changed, the scsi, the motherhoard (mice?), the tape drive?

I use the generic scsi driver, it's just generic but works great for my purposes.

https://sg.danny.cz/sg/sg_v40.html

When I modprobe sg, it doesn't say anything which means that sg IS loaded. So my generic tape driver is loaded. The question is why can't my machine see a tape drive?

It's a hardware issue - not good. The sg driver is loaded but can't find a tape drive.

So it's lights 1 and 3. I need to get the tech manual?

Yes, check the manual

I now realize it might be a lights 1 3 but a beep of 1 - 3 - 2. Looking this up, it might be a memory problem. My comupter beeped 6 times but it beeps 1 - 3 - 2.

so tomorrow I'll reseat the memory chips and maybe that will solve the problem. My question would be though, what caused the issue to begin with? Maybe I can
buy new memory if it's defective but the PC is kind of old.

I'll see tomorrow. But it's definitely appears to be memory - I have the exact diagnostic of a memory problem. That's better than a graphics card problem usually.