Sitescope 11.24 unable to connect to remote ubuntu server

Hi,

I've been trying to add a Ubuntu remote host to Sitescope but get the error: remote command error  (-1)

Error Log shows:

2017-10-31 09:08:07,317 [http-8080-Processor17] (RemoteCommandLine.java:263) INFO  - rem: <HOSTNAME> -->close ssh connection
2017-10-31 09:08:07,317 [http-8080-Processor17] (SSHJavaClient.java:136) DEBUG - Machine <HOSTNAME> Done with internal connect, status = -1000
2017-10-31 09:08:07,317 [http-8080-Processor17] (SSHRemote.java:532) DEBUG - SSHManager Info: create session: java for remote: <HOSTNAME> failed!
2017-10-31 09:08:07,317 [http-8080-Processor17] (RemoteCommandLine.java:128) ERROR - list of SSH retries -->
2017-10-31 09:08:07,317 [http-8080-Processor17] (RemoteCommandLine.java:129) ERROR -
Tue Oct 31 09:08:07 WST 2017 SSH internalConnectV2: A Connection error occurred: Key exchange failed:
I/O error3: An established connection was aborted by the software in your host machine (uc) dI <I/O error3: An established connection was aborted
by the software in your host machine> dI.notify false <null> wFKC.waited false true wFKC.done <false> connecting to host <HOSTNAME> 2017-10-31 09:08:07,317 [http-8080-Processor17] (RemoteCommandLine.java:130) ERROR - <-- list of SSH retries 2017-10-31 09:08:07,317 [http-8080-Processor17] (SSHRemote.java:399) DEBUG - SSH result after parsing = []

I am able to SSH to the ubuntu host from the Sitescope (windows) host. We have  other Ubuntu hosts connected OK.

I'm unsure why this host is not working. I'd appreciate any advice!

<Edit>
I've learnt that the client has added kerberos to this particular host. How does sitescope handle this?