OpenNebula: Can't create a host - Could not resolve hostname

Question

I'm having trouble launching a host in Open nebula. Is is because I can't merge the front end with hosts i.e start off with one server and build from there. Do I have to start with 3 or 4 servers?

My error log when I try to create a host:

Fri Mar  8 15:14:21 2013 [ReM][D]: TemplatePoolInfo method invoked
Fri Mar  8 15:14:23 2013 [ReM][D]: GroupPoolInfo method invoked
Fri Mar  8 15:14:26 2013 [ReM][D]: HostAllocate method invoked
Fri Mar  8 15:14:27 2013 [ReM][D]: HostInfo method invoked
Fri Mar  8 15:14:27 2013 [InM][I]: Monitoring host bac (3)
Fri Mar  8 15:14:28 2013 [InM][I]: Command execution fail: scp -r /var/lib/one/remotes/. bac:/var/tmp/one
Fri Mar  8 15:14:28 2013 [InM][I]: ssh: Could not resolve hostname bac: Name or service not known
Fri Mar  8 15:14:28 2013 [InM][I]: lost connection
Fri Mar  8 15:14:28 2013 [InM][I]: ExitCode: 1
Fri Mar  8 15:14:28 2013 [InM][E]: Error monitoring host 3 : MONITOR FAILURE 3 Could not update remotes

Answer 1

This is one of the most common pitfalls when configuring for the first time an host.

The documentation states:

Before adding a host check that you can ssh to it without being prompt for a password

You can simply check for DNS configuration problems trying to connect to the remote host using the same hostname you would add with the onehost create command, from the oneadmin shell:

$ ssh bac

If you can reach the remote host shell, you are done. If not, check about your DNS configuration (or you may add a line in /etc/hosts)

Answer 2

You can start with only one server. Your problem is name resolution:

Fri Mar 8 15:14:28 2013 [InM][I]: ssh: Could not resolve hostname bac: Name or service not known