According to all responses it seems that the topic is not so simple and there are some conditions which need to be met to keep raspi lets say "stable".
1) Some of you mentioned that my GOODRAM microSDHC 32GB CL10 ( bought from Raspberry Pi Approved Reseller ) is not good.
Let me buy microSDXC. Let's see if it would solve the problem.
2) Recommended Power supply 5.1V - 3A. Got it already.
3) Devices connected to Raspberry PI.
In my case I have only one HDD connected : WD Elements 2621 2TB. The disk is powered by RasPI via USB3.
This is interesting. I'm in 99% sure that after "shutdown -h now" I see only red LED flashes constantly.drgeoff wrote: ↑Mon Jun 14, 2021 12:00 amYes but are you waiting long enough for that to complete before pulling the power plug? When the green LED has flashed regularly 10 times you can safely remove power.
Nevertheless some of you confirmed that NAS solution works fine so I see light in the tunnel. There is a hope