I'm not sure what is going on, but I think its kernel panics going on. When my Pi is running, all it is running is Plex Media server within Raspbian. Normally its fine, however, if I am logged in through ssh and just have the window open in the background, I'll get errors. They all start with "kernel" and have a long list of numbers and letters, some of them in brackets. It doesn't shut down the Pi, doesn't reboot or anything, keeps going fine.
Since Plex is the only thing I use, I sometimes have to login to restart plex (sudo service plexmediaserver restart) and sometimes I'll just restart the whole system (sudo reboot).
I've tried doing (sudo apt-get update) and (sudo apt-get upgrade) but neither of them change anything and the kernel messages still happen.
I think it might be a bad microSD card, which if it is, I'll just get a new microSD card and reinstall the system from scratch. I don't have that much on there to lose anyway, its literally just raspbian, Plex, netatalk (for mounting the drive on my Mac) and the ntfs drivers to read the external drive. That's really it.
Any ideas? I had thought a kernel panic could be remedied by updating/upgrading, but that hasn't happened. This has been going on for as long as I've had the Pi up and running, which admittedly has only been about a month.
If its a bad microSD card, that's easy enough to fix and cheap. If there's some bigger problem, I'll have to figure out what could be going on.
System is a Pi 3, connected to the network through wifi, with just one external 4TB hdd connected to it that had been running fine with other SD cards, which is why I think its probably the card, so confirmation would be nice.