UNIX for Dummies Questions & Answers

Hello all,

I would like to know if anyone had ever set up a network in which they used DHCP and OPENSSH with no password. I can configure my ssh files to allow me to enter any machine without a password as long as I have generated the public and private keysa nd store them in my .ssh/aut... But what would happen if the IP is changed? Will I have to regenerate the public and private keys? Is there a way in which I can pre generate the keys and just mv it to the server after it gets it new IP?

Thanks

Yes, I have used SSH with and public-private key pair with no password. It works great if you don't mind the risk of someone gaining access to your machine.

For example, if your machine is already password protected (like a login password), you might consider the benefits of a key pair without a password if you login to a remote server with SSH often.

Yes, you will have to regenerate keys if you change IP address on either the server or the client.

I don't think there is an easy way to pregenerate keys, but you might find a way. If you do, please post how to do it.

Neo

You will need to create a public/private key pair to use for authentication (look up ssh-keygen). This will allow a connection to the remote machine based upon RSA or DSA authentication instead of a password. If a passphrase is used in ssh-keygen, the user will be prompted for a password each time in order to use the private key.

With ssh2 I would recommend creating DSA keys using the procedure below. This will create a public/private DSA key for use in ssh2 sessions only. The public key is stored in ~/.ssh/id_dsa.pub, while the private key is in ~/.ssh/id_rsa. DSA public keys are placed in ~/.ssh/authorized_keys2 on the remote machine.

ssh-agent(1) and ssh-add(1) are utilities used in managing multiple passworded private keys.



Create your own DSA keys. Step-by-step instructions:

1. Run ssh-keygen -t dsa -N '' on your source host (creates a key with No Passphrase).

2. copy $HOME/.ssh/id_dsa.pub to $HOME/.ssh/authorized_keys2 on your remote host

3. chmod your $HOME/.ssh directory to be read/write/execute for only the owner (chmod -R 700 .ssh)

4. Make sure you _really_ are running ssh2 when connecting (Usually this is the default setting).

bostontechgrou,
Thanks but I have already done this. I just wanted to know if there is any way to do it when the IP is change after you have generated the keys. Say for a DHCP client after reboot and a new IP is assigned.