I'm constantly setting up passwordless ssh environments. And, while there are many howTos out there, most are rather long. This is going to be very short and without much explanation. Read the load documents for the details. I plan to add screen-shots, but that has to wait until after my wrist heals. I broke it badly just the day before yesterday.
PuTTY doesn't natively support the private key format (.pem)
You must convert your private key into a .ppk file
before you can connect to your instance using PuTTY
ssh-keygen generates 2 files.
- id_rsa: The private key
- id_rsa.pub: The public key
PuTTYgen will genrate the ppk for use with PuTTY.
On Linux (I’m using CentOS 8)
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mkdir -p ~/.ssh
chmod 700 ~/.ssh
cd ~/.ssh
ssh-keygen -t rsa -b 4096 -N '' -f ~/.ssh/id_rsa -C "yourEmailAddr@yahoo.com"
cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
chmod 400 ~/.ssh/*
cp ~/.ssh/* /VMShare/ssh/ #a common mount between my virtual machines and windows
on Windows
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1. open PuTTYgen Click Load and open the private file (normally id_rsa)
2. Click “Save Private Key” and choose a name. I use id_rsa.ppk
3. Open Putty
3.1. Set Connection->Data->Auto-login username as appropriate
3.2. set the Connection->SSH->Auth->”Private key file for authentication” to the ppk file.
To setup 1 way ssh between 2 Linux machines
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copy the id_rsa file to ~/.ssh on the second machine
Next: chmod 400 ~/.ssh/id_rsa
Now you can ssh from the second machine to the first
To setup 1 way ssh between 2 Linux machines
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Copy the id_rsa and id_rsa.pub file to ~/.ssh on the second machine
cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
chmod 400 ~/.ssh/authorized_keys ~/.ssh/id_rsa ~/.ssh/id_rsa.pub
To Test the ssh use:
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ssh -i id_rsa.pub user@host1
<https://help.dreamhost.com/hc/en-us/articles/215464758-How-do-I-set-up-passwordless-login-in-PuTTY->