Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

I need to connect to hostB using user2 from hostA where I´m connected using user1.

I've run ssh-keygen for user1 on hostA and copied the public key generated in id_rsa.pub to the authorized_keys of user2 in hostB.

Then I tried to connect from hostA to hostB using the command:

   $user1@hostA> ssh user2@hostB

I still get a request for password:

   user2@hostB's password:

If I try to connect using the same user on both hosts, it works correctly:

   $user1@hostA> ssh user1@hostB
   Enter passphrase for key '/home/user1/.ssh/id_rsa':

What am I missing?

share|improve this question

3 Answers 3

up vote 2 down vote accepted

sshd will ignore your files if it doesn't like the permissions. I was able to duplicate this behavior by setting "user2"s ~/.ssh directory world writable.

share|improve this answer
    
You were right, my problem were the permissions. When I set the permissions according with what is recommended in the OpenSSH FAQ item 3.14, it worked. openssh.org/faq.html#3.14 –  lpacheco Jan 11 '11 at 15:38

You need to tell your ssh to use the private key of user2 instead of yours (user1):

$user1@hostA> ssh -i /path/to/private_key_of_user2 user2@hostB

share|improve this answer
    
notice that you can debug with ssh -vvv <rest of command> and you will see which keys are tested, @desasteralex solution should be ok as you force the key used, without informations several key are used, maybe not the one you want. –  regilero Jan 10 '11 at 21:42
    
@regilero: Agree, but I came to the conclusion that lpacheco is using several keys already, see: "$user1@hostA> ssh user1@hostB". The public key of user1 already exists in the authorized_keys file on hostB, and so the user does on hostB. –  desasteralex Jan 10 '11 at 21:59
    
If I owned both accounts, I could do that, but I own user2 and want to allow user1 to connect as user2 in a single machine. I understand that if I give user1 the private key of user2, he would be able to connect as user2 to any other machine that user2 has access, right? –  lpacheco Jan 11 '11 at 15:46
    
@Ipacheco: Yes, if user1 got the private key of user2, he/she can connect to every machine on which the public key of user2 has been added to the authorized_keys file. Exception: user1 needs to know the username of user2 on the destinated machine (depends on into which users authorized_keys file you've placed the public key). –  desasteralex Jan 11 '11 at 23:07

You could also place the pub key of user1 in the authorized_keys file of user2 on hostB.

share|improve this answer
    
That's what I did, but it isn't working. –  lpacheco Jan 11 '11 at 9:39

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.