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Omar95's avatar
Omar95
Icon for Altostratus rankAltostratus
Feb 04, 2021

AWS - AFM SSH Proxy error SSH authentication

Hello all,   I follow the documentation of F5 to implement the SSH proxy : https://techdocs.f5.com/kb/en-us/products/big-ip-afm/manuals/product/big-ip-network-firewall-policies-and-implementatio...
AFM
AWS
security
Martin_Vlasko's avatar
Martin_Vlasko
Icon for Altocumulus rankAltocumulus
Apr 08, 2021

Hi Omar,

I experienced the same error message.

Assuming you have already generated the RSA key pair on your backend server...

On your backend server, go to /etc/ssh/sshd_config and make sure that the following line is NOT commented. Don't forget to restart the SSH service afterwards!

HostKey /etc/ssh/ssh_host_rsa_key

On your backend server, copy the SSH public key from /etc/ssh/ssh_host_rsa_key.pub, and make sure you do NOT include the trailing description, so it should look something like:

ssh-rsa AAAAB3Nza....oC/arKVST/r9

And NOT like:

ssh-rsa AAAAB3Nza....oC/arKVST/r9 root@ubuntu

Copy this backend server's RSA public key to the Real Server Auth Public Key section of the SSH Proxy Key Management.

Next, copy the F5's own RSA private key (to be found in /root/.ssh/id_rsa) to the Proxy Server Auth Private Key section of the SSH Proxy Key Management. If you do not yet have it, run the ssh-keygen as per SSH Proxy documentation.

It does work for me, hope it helps you too.

Cheers,

Martin