SSH Setup

On this page, you will configure SSH on your cluster so that the Nimbus components can properly and securely communicate.

SSH

The Nimbus service and VMM nodes communicate via SSH, so you must set up password-less SSH keys. At this point you should have two nodes set up, each with a privileged account (probably, but not necessary called nimbus). You need to allow the service node account to SSH to the VMM, and vice versa.

There are several ways to set this up, but the easiest way is to generate keys on each node and append the public keys to each others ~/.ssh/authorized_keys files. For example:

Generate an SSH keypair on the service node, taking care to NOT specify a password.

nimbus@service $ ssh-keygen

Copy the generated public key to the VMM node and then login there directly

nimbus@service $ scp ~/.ssh/id_rsa.pub nimbus@vmm1:service_rsa.pub

nimbus@service $ ssh nimbus@vmm1

Append the service node's key to the authorized_keys file

nimbus@vmm1 $ cat service_rsa.pub >> .ssh/authorized_keys

Now generate a key pair for the VMM node itself and exit back to the service node

nimbus@vmm1 $ ssh-keygen

nimbus@vmm1 $ exit

Fetch the VMM's public key and authorize it (you should not be prompted for a password during the scp transfer).

nimbus@service $ scp nimbus@vmm1:~/.ssh/id_rsa.pub ./vmm1_rsa.pub

nimbus@service $ cat ./vmm1_rsa.pub >> .ssh/authorized_keys

You should now be able to freely SSH between the service and VMM nodes. Note that as you add more VMMs in the future, you will need to ensure that SSH works in the same way for each.

Autoconfig

Nimbus includes a configuration program that checks for a properly functioning SSH setup and configures your first VMM node into the service. The script is interactive and will go through a series of questions and tests before it makes any changes. If you make a mistake, just hit Ctrl-C and start over.

In order to add the VMM node, this tool needs the Nimbus service to be running. If it is not, you will be given a command to run later once you start the service. 
$ cd $NIMBUS_HOME

$ ./bin/nimbus-configure --autoconfig

Afterwards, restart the Nimbus services in order for changes to take effect. 

$ $NIMBUS_HOME/bin/nimbusctl services restart

The last thing the autoconfig script does is disable fake mode on the service. Which means that you are ready for a real test, using the cloud client to launch a real virtual machine! Proceed to the next page, Final Tests.