Host Key uniqueness

From: José Arango (arango_at_caribe.net)
Date: 03/26/04

  • Next message: Kapil: "Problem with using same dsa hostkeys on 2 different machines, one of which is backup" 
    Date: Fri, 26 Mar 2004 00:56:52 -0400

    Hello everyone,

    I'm learning about ssh. I still don't have clear the host key technique. I
    know its purpose. I just would like to know what prevents server YYY from
    taking server XXX's host key...so that when server YYY tries to impersonats
    XXX server...all of its (ssh-client) users would connect to YYY without
    noticing that in fact is another server.

    Another example, If I connect to server XXX, I'll have the server host key
    in my .ssh directory. Can I just take that key and configure my SSHD so it
    will use that key as my host key? I know that the host key is generated
    based on hostname, ip address etc...but once is generated..what prevents me
    to take another server's key and use it as if it were mine?

    I'll be glad if someone can explaint it to me.

    Thanks in advance,
    Jose

  • Next message: Kapil: "Problem with using same dsa hostkeys on 2 different machines, one of which is backup"

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