No, it's not harmful to disconnect your Ethernet cable from your PC while it's operating.
No, it's not harmful to disconnect your Ethernet cable from your PC while it's operating.
It doesn't harm anything. It's similar to unplugging a USB device.
A bit of online activity might appear but overall everything is okay.
Most components on the back of a PC are built to be easily swapped out. In the past, removing a PS/2 mouse while the computer was running could damage the motherboard, but those situations are rare now. Currently, boards that support PS/2 devices still don’t allow hot swapping. You can’t link or unlink a device while the system is running. Regarding Ethernet, it’s meant to be connected or disconnected during operation.
Actually, I'd argue that it is bad. You will not damage the computer hardware, but depending on what you're doing you may actually drop important connections. It's going to be less bad that pulling out a USB drive, but there is still the possibility of corrupting a file that is mid-transfer, or interrupting your connection to the local Minecraft server - That's why the connections have a locking tab, you don't want the connection just popping out randomly. In all seriousness though, you won't break anything. If you do a quick swap of a cable to change ports or something you *may* have a program complain about the interruption, but you can usually resume a download where it left off, and if you're using an application that is particularly sensitive to network drops (Like SSH or IRC) you'd probably know about it, so just close your sessions before yanking on the cord.