sshd[pid]: error: Could not load host key: /etc/ssh/ssh_host_ecdsa_key

Project:Linux server
Component:Documentation
Category:support request
Priority:normal
Assigned:Unassigned
Status:active
Project wiki:Server
Description

I get this error in my server logs each time I connect:

sshd[pid]: error: Could not load host key: /etc/ssh/ssh_host_ecdsa_key

What is it about?
Implications?
How to fix it?

(+ fix components for this project).