How to store rsa keys?

Question

linux

Good evening!
Generated keys and my public key was added to the server. Only one. But I want to go there from several machines, a laptop, a workstation, virtual machines.
How to be? Just save the keys on a flash drive, copy them everywhere, setting the appropriate rights with chmod? But security in this case will be close to zero, like the security of my passwords.txt file on the desktop. What to do, how to make it possible to use only one pair for many devices without losing security.

Answer 1

Already have access? Run the command as many times as you have keys:

$ ssh [email protected]_IP_VPS
$ echo “ВСТАВЛЯЕМ СОДЕРЖИМОЕ ФАЙЛА КЛЮЧА” >> ~/.ssh/authorized_keys

Answer 2

Use E-Token/Rutoken etc. https://ru.wikipedia.org/wiki/EToken externally like a flash drive, inside a private key. The key is not extracted, the generation takes place inside the device, the output is only a signature.
According to the experience of use, I can say the following: before starting - dancing with a tambourine until you figure it out, but then a high level of security, in case of loss you can be calm, 3 attempts to enter a pincode, then 10 long pakkoda, used up - got a brick.

Answer 3

The private key can be encrypted with a password. Then even if an attacker steals a flash drive, he will not be able to use the key.

Answer 4

Your key has been added --> you have access to the server --> you can add as many keys as you like. Is not it so?