I changed the config file to:
Host gdl57                        
    HostName gdl57.dekko-1        
    User rob                      
    IdentityFile ~/.ssh/rob_gdisys
Apparently the ssh daemon did stop.
Windows:
PS C:\WINDOWS\system32> Get-Service sshd
Status   Name               DisplayName
------   ----               -----------
Stopped  sshd               OpenSSH SSH Server
PS C:\WINDOWS\system32> Start-Service sshd
PS C:\WINDOWS\system32> Get-Service sshd
Status   Name               DisplayName
------   ----               -----------
Running  sshd               OpenSSH SSH Server
Now I am getting
IBM i:
ssh -v gdl57                                                                         
  OpenSSH_8.0p1, OpenSSL 1.1.1c  28 May 2019                                           
  debug1: Reading configuration data /home/ROB/.ssh/config                             
  debug1: /home/ROB/.ssh/config line 1: Applying options for gdl57                     
  debug1: Reading configuration data /QOpenSys/QIBM/ProdData/SC1/OpenSSH/etc/ssh_config
  debug1: Connecting to gdl57.dekko-1 [10.10.9.30] port 22.                            
  debug1: Connection established.                                                      
  debug1: identity file /home/ROB/.ssh/rob_gdisys type 0                               
  debug1: identity file /home/ROB/.ssh/rob_gdisys-cert type -1                         
  debug1: Local version string SSH-2.0-OpenSSH_8.0                                     
  debug1: Remote protocol version 2.0, remote software version OpenSSH_for_Windows_7.7 
  debug1: match: OpenSSH_for_Windows_7.7 pat OpenSSH* compat 0x04000000                
  debug1: Authenticating to gdl57.dekko-1:22 as 'rob'                                  
  debug1: SSH2_MSG_KEXINIT sent                                                        
  debug1: SSH2_MSG_KEXINIT received                                                    
  debug1: kex: algorithm: curve25519-sha256                                            
  debug1: kex: host key algorithm: ecdsa-sha2-nistp256                                                                             
  debug1: kex: server->client cipher: chacha20-poly1305@xxxxxxxxxxx MAC: <implicit> compression: none                              
  debug1: kex: client->server cipher: chacha20-poly1305@xxxxxxxxxxx MAC: <implicit> compression: none                              
  debug1: expecting SSH2_MSG_KEX_ECDH_REPLY                                                                                        
  debug1: Server host key: ecdsa-sha2-nistp256 SHA256:euodvI3161T4admEYhBIaF8Zfv1ZBhur7gt4gNKAXHI                                  
  debug1: Host 'gdl57.dekko-1' is known and matches the ECDSA host key.                                                            
  debug1: Found key in /home/ROB/.ssh/known_hosts:2                                                                                
  debug1: rekey out after 134217728 blocks                                                                                         
  debug1: SSH2_MSG_NEWKEYS sent                                                                                                    
  debug1: expecting SSH2_MSG_NEWKEYS                                                                                               
  debug1: SSH2_MSG_NEWKEYS received                                                                                                
  debug1: rekey in after 134217728 blocks                                                                                          
  debug1: Will attempt key: /home/ROB/.ssh/rob_gdisys RSA SHA256:2qf7C4xsg7iyCSOe447JsaHoRAkS88FCSwcxBAJ6W1Y explicit              
  debug1: SSH2_MSG_EXT_INFO received                                                                                               
  debug1: kex_input_ext_info: server-sig-algs=<ssh-ed25519,ssh-rsa,rsa-sha2-256,rsa-sha2-512,ssh-dss,ecdsa-sha2-nistp256,ecdsa-sha2
  -nistp384,ecdsa-sha2-nistp521>                                                                                                   
  debug1: SSH2_MSG_SERVICE_ACCEPT received                                                                                         
  debug1: Authentications that can continue: publickey,password,keyboard-interactive                                    
  debug1: Next authentication method: publickey                                                                         
  debug1: Offering public key: /home/ROB/.ssh/rob_gdisys RSA SHA256:2qf7C4xsg7iyCSOe447JsaHoRAkS88FCSwcxBAJ6W1Y explicit
  debug1: Authentications that can continue: publickey,password,keyboard-interactive                                    
  debug1: Next authentication method: keyboard-interactive                                                              
  debug1: Authentications that can continue: publickey,password,keyboard-interactive                                    
  debug1: Next authentication method: password                                                                          
  debug1: read_passphrase: can't open /dev/tty: No such device or address                                               
  rob@gdl57.dekko-1's password:                                                                                         
Basically it tried the key but stops at prompting for the password.
How do I tell why it didn't like the key?  Is it a bad cipher or some such thing?
Rob Berendt
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