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InnO's avatar
InnO
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Jul 11, 2016

SCP not working anymore since upgrade to 12.1

Hi,

 

I recently upgraded my Big-IP from 11.6 HF6 to 12.1 successfully. However, I am not able anymore to execute scp commands which I used to transfer my ucs backups remotely. Any attempt always end up with a "no hostkey alg" error. I tried many different things like regenerating rsa and dsa keys like I always do after an upgrade, but as of today have been unsuccessful...

 

Any advice someone ?

 

Thanks, Pascal.

 

  • Try this...

     

    ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key

     

    ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key

     

    • InnO's avatar
      InnO
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      Thanks, but tried that already, with no success. There was no ssh folder under /etc by the way...

       

  • Try this...

     

    ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key

     

    ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key

     

    • InnO's avatar
      InnO
      Icon for Nimbostratus rankNimbostratus

      Thanks, but tried that already, with no success. There was no ssh folder under /etc by the way...

       

  • InnO's avatar
    InnO
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    Not sure that can help but, but here is a verbose output for the scp :

     

    • dexterstu's avatar
      dexterstu
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      Ran into this same issue and we were also using Bitvise SSH Server.

       

      Beginning in BIG-IP 12.1.0, the BIG-IP system no longer supports DSA keys for SSH connections (as it is using OpenSSL 7.0).

       

      https://support.f5.com/kb/en-us/solutions/public/k/40/sol40220910.html

       

      The problem for us was with the host key that the SSH server was presenting, not the keys that were generated on the F5 for authentication. The Bitvise SSH Server was presenting a DSA host key, which is no longer supported.

       

      Fix was to generate a new Host key from within Bitvise Control Panel (Manage Host Keys --> Generate New --> Employ) using the RSA Algorithm.

       

      You may also need to clear the existing host key on the F5 by removing the relevant entries (or deleting the whole file) from /root/.ssh/known_hosts

       

    • InnO's avatar
      InnO
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      Hi Stuart, just forgot to put an update on that case, but that is exactly what I did too to fix that issue :)

       

      Thanks, Have a good one,

       

      Pascal.