Fatal Error When Downloading BTC Block Chain (Help Needed)

[Mists]

Bitcoin Core 27.1 (linux tgz 64bit)
Linux Mint Cinnamon 22
Intel Core i5-7300U CPU @ 2.60GHz × 2, memory 15.5 GiB, Hardrive 512.5GB (plus external samsung T7 SSD for Bitcoin core installation).
The BTC core GUI threw up a fatal error with roughly 7hrs of DL left of the block chain! Plus my external SSD was no longer visible on the computer (so I yanked it out and re-connected and then it became visible again).
Beginning of debug.log: https://pastebin.com/Zg8ZCDQ6

FYI: I am a novice at Linux and a journeyman at best with IT 
Thanks

[achow101]

USB is not always reliable. The error likely occurred when the drive could no longer be reached.

[Mists]

Thanks for the quick reply! Do I just relaunch btc core and start again then? Or could it be that I can pick up the dl where it left off? Not sure how to proceed…

[DireWolfM14]

As long as the most recent block didn't get corrupted it should pick up where it left off.  If it doesn't work you can try deleting the most recent block and chainstate (.ldb) files, and it should be able to recover after that.

The files are most likely in the directory paths below:

/home/<USER>/.bitcoin/blocks/
/home/<USER>/.bitcoin/chainstate/

[Mists]

Thanks very much, when I saw the word “fatal” I feared the worst. But I will try your suggested actions and report back.

[philipma1957]

Thanks very much, when I saw the word “fatal” I feared the worst. But I will try your suggested actions and report back.

Follow up and let us know please.

[LoyceV]

USB is not always reliable.

I only recently found out there's a huge difference in cables used: I have some old external drives that already disconnect when I look at them, and I have other drives that work totally fine.
But still, I wouldn't use an external disk for continuous reading and writing. If at all possible, OP should install an internal disk.

[nc50lc]

(so I yanked it out and re-connected and then it became visible again)

Not sure how to proceed…

First step should be: replace the USB Cable and/or USB port. If it happened once, it may happen again.
Frequent unexpected removal of your external drive could cause data corruption at some point.

(LoyceV beats me to it, about the cable)

Or could it be that I can pick up the dl where it left off?

It will, but if there's a corruption, Bitcoin Core will detect it and will suggest you to reindex which wont be as slow as IBD.

It's a good thing that your blockchain isn't "pruned":

Code:

2024-08-18T19:02:25Z Setting NODE_NETWORK on non-prune mode

Otherwise, a corrupted chainstate or block will require you to start from scratch.

[Mists]

Thanks all for the advice. I really appreciate all your responses. I'm kind of committed at this point to the external SSD but I will make it a priority to upgrade in the future. So the problem did repeat itself a few more times (luckily there was no corruption), but i have now managed to DL the chain and BTC core is running happily at the moment. The issue may have been (bear in mind I'm no expert) that the USBC connection was letting me down thanks to the UAS protocol... because when I switched to a old style USB connection the rest of the DL went fine and my node is running fine at the moment. I wonder if the heightened demand of the DL also played a part? Suffice to say that using an external drive may be more trouble than its worth.

[odolvlobo]

Another possibility is insufficient power. As an example, I learned the hard way that a RPi 4 is not able to power 2 Samsung T7s. To fix the problem, I had to get a powered USB hub.

[LoyceV]

Another possibility is insufficient power. As an example, I learned the hard way that a RPi 4 is not able to power 2 Samsung T7s. To fix the problem, I had to get a powered USB hub.

USB sometimes just doesn't make sense: I have old HDD cases that have a very hard time getting the disk spinning, and when I put the same disk in a new case it works just fine (on the same USB port's power).

I'm kind of committed at this point to the external SSD but I will make it a priority to upgrade in the future.

I've used external drives when dealing with Fork claiming. Let me put it this way: I'd rather prune the blockchain than running it from an external disk long-term.