Limit backup disk usage rate

Sometimes you don't want to utilize disk too heavy.

My case was not to alert monitoring on disk i/o trigger (and yes, this is a workaround, in common case you'd probably like to modify alert setting instead). I tried nice, ionice and even systemd-run -p "IOWriteBandwidthMax=/dev/sdX 10M …

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SSH host behind NAT

Today I solved task of establishing persistent SSH tunnel from NAT-ted host to local machine.

The problem is that Host B is supplied with dynamic IP, so you can't just connect to it.

[A] -X-> [B]
me       target

I decided to reverse the process and force Host B to contact …

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10 console utilities challenge

I was asked to name 10 linux console commands/utils consist of 3 symbols. To be honest, I ended up about 7-8 of those.

After couple of minutes at home I managed to beat this challenge, here's my list:

cat/tac
top
tar/dar/zip
git
vim
ldd
sed/awk …
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Linux boot stages

How does linux boots up, from power button to running services.

Power button

When you pressed power button, current runs through circuits over the motherboard and boot process starts.

It also could be magic packet sent via network or some other remote start method. Let's say, command sent from IPMI …

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