Glassfish cluster ssh node. Subsystem request failed error when creating a ssh node

Recently I stumbled upon a nasty and obscure error while configuring a glassfish 3.x cluster

I had all my ssh configuration properly in place with all my ssh keys between my nodes I could connect with no issues between the different machines by executing the ssh command :

[user@das~]$ssh machine1.com 

Even when I executed the asadmin command to setup the ssh configuration on the remote server everything comes up normally :

[user@das~]$ ./asadmin setup-ssh machine1.com
Successfully connected to user@achine1.com using keyfile /home/user/.ssh/id_rsa
SSH public key authentication is already configured for user@achine1.com
Command setup-ssh executed successfully.

But every-time I wanted to add a ssh node either by using the asadmin tool or the glassfish administration console I kept getting the following error message :

[user@das~]$ asadmin create-node-ssh --nodehost=machine1.com node1
remote failure: Warning: some parameters appear to be invalid.
SSH node not created. To force creation of the node with these parameters rerun the command using the --force option.
Could not connect to host machine1.com using SSH.
The subsystem request failed.
The server denied the request.
Command create-node-ssh failed.

Side-note: If you use the --force parameter as suggested by the asadmin tool, the create-ssh-node command will end successfully but problems will arise later

After searching for a bit I realized that the problem was with SSH configuration and not a really a glassfish error

As it turns out my hosting provider had disabled SFTP on the target machine's ssh configuration. Once found the solution was pretty simple, just un-comment or add the following line to your ssh_config file

Subsystem       sftp    /usr/libexec/openssh/sftp-server

You will probably need to restart sshd on the target machine

Once the sshd restarted head back to the DAS machine and try to create the ssh node again, if everything goes as planned you should get a similar output to this :

[das]asadmin create-node-ssh --nodehost=machine1.com node1
Command create-node-ssh executed successfully.