Xen Cluster Management With Ganeti On Debian Etch - Page 6
11 Initializing The Cluster
Now we can initialize our cluster (this has to be done only once per cluster). Our clustername is cluster1.example.com, and I want node1.example.com to be the master, therefore we run the following command on node1.example.com:
gnt-cluster init cluster1.example.com
12 Adding node2.example.com To The Cluster
Now that node1 is the master, we run all commands for managing the cluster on node1. In order to add node2.example.com to the cluster, we run:
gnt-node add node2.example.com
This will look like this:
node1:/srv/ganeti/os# gnt-node add node2.example.com
Now let's check if our cluster really consists out of node1 and node2:
You should get something like this:
node1:/srv/ganeti/os# gnt-node list
13 Setting Up An Instance
Now let's create our first virtual machine (called an instance in Ganeti speak), inst1.example.com. I want to use DRBD for it (remote RAID1), I want node2 to be the primary node, and I want the instance to have a 5 GB hard drive, 256 MB swap and 64 MB RAM. Again, we run the command on the cluster master, node1.example.com:
gnt-instance add -t remote_raid1 -n node2.example.com --secondary-node node1.example.com -o debian-etch -s 5g --swap-size 256 -m 64 inst1.example.com
This can take some time. This is how the output looks:
node1:~# gnt-instance add -t remote_raid1 -n node2.example.com --secondary-node node1.example.com -o debian-etch -s 5g --swap-size 256 -m 64 inst1.example.com
Ganeti has created a complete virtual machine (using Debian Etch) which you can now use.
14 Configuring The Instance
To get to inst1.example.com's command line, run
gnt-instance console inst1.example.com
Now you can log in to inst1.example.com. The username is root along with no password. Therefore the first thing we do after the login is create a password for root:
Next we must add a stanza for eth0 to /etc/network/interfaces. Right now, inst1.example.com has no network connectivity because only lo (the loopback interface) is up.
As I said in chapter 1, I want inst1.example.com to have the IP address 192.168.0.105:
Restart the network afterwards:
to update the packages database on inst1, and then install OpenSSH and a full-featured vim:
apt-get install ssh openssh-server vim-full
Now you can connect to inst1.example.com using an SSH client such as PuTTY on the IP address 192.168.0.105.
To leave inst1's console and get back to node1, type CTRL+] if you are at the console, or CTRL+5 if you're using PuTTY (this is the same as if you were using Xen's xm commands instead of Ganeti).