===== SSH key ecdsa =====

If you have such kind of error in syslog
<code>
auth|security:err|error sshd[23003268]: error: Could not load host key: /etc/ssh/ssh_host_ecdsa_key
sshd[5898336]: error: Could not load host key: /etc/ssh/ssh_host_ecdsa_key
</code>

You need just to configure an ECDSA key:
<cli prompt='#'>
[root@nim] /root # ssh-keygen -t ecdsa -b 521  -f /etc/ssh/ssh_host_ecdsa_key
</cli>

Or without passphrase and no confirmation: 
<cli prompt='#'>
[root@nim] /root # echo |ssh-keygen -q -t rsa -N ''
</cli>

Read an SSH key to find the type and lengh
<cli prompt='#'>
[root@aixtest] /root/.ssh# ssh-keygen -lf id_rsa.pub
4096 SHA256:y+eCN/wHa2+y4zNSTapuxxxxxxxxkWR2NIvKzwGFM root@aixtest (RSA)
</cli>