ssh login from NIM server is failing with error "no matching host key type found. Their offer:ssh-rsa,ssh-dsa"

 Error statement: login from NIM server is failing with error "no matching host key type found. Their offer:ssh-rsa,ssh-dsa", openssh version , OpenSSH 6.01P1(2012) era does not support newer key exchange algorithm.

Error details:

NIM_jump_server# ssh padmin@vioserverIP/FQDN

When user tried to login VIO padmin user using passwordless ssh throwing below error.

"no matching host key type found. Their offer:ssh-rsa,ssh-dsa", openssh version , OpenSSH 6.01P1(2012) era does not support newer key exchange algorithm.

Reason for this error:

• VIOS is running OpenSSH 6.0p1
• That version only supports legacy host key types:

  • ssh-rsa
  • ssh-dsa 

Solution to this problem:

1. Upgrade the version of OpenSSH which support newer key exchange algorithm. OpenSSH 7.5P1 supports newer key exchange algorithm.

2. use following command for workaround solution if OpenSSH version upgrade not possible immediately.

 NIM_jump_server# ssh -o HostKeyAlgorithms=ssh-rsa -o PubkeyAcceptedAlgorithms=ssh-rsa padmin@<VIOS-host-or-IP>

reason for using above command: older VIOS/OpenSSH versions only support the legacy ssh-rsa host key and/or public‑key signature.

Thanks!!!!