Saturday, November 12, 2016

Multi node openstack newton installation on centos 7


Installing a multi node open stack newton on centos 7
In your vmware workstation create a custom nat network and a lan segment.
Create 3 VMs with the following VM settings ( do not power on yet) and mount the centos 7 image.
Controller

Compute

Neutron



Using the nmtui (network manager) command assign a private network (lan segment) ip to all of the VMs. 10.10.10.10/24 to the controller, .20 to compute, .30 and .40 to neutron. You can only assign the ip address and leave everything else as default. You may also name these interfaces as tunnel and the interface where the primary ip resides (from nat on vmnic0 or network interface 1) as management.
Run
Ip addr
On all of them and make a note of the ip address of all and prepare a hostfile like this
<ip addr> controller.home.com controller
<ip addr> compute.home.com compute
<ip addr> neutron.home.com neutron

Note: I was using a windows dns server but since the controller node was unable to reach the compute and neutron hosts with their netbios/short names for some reason it always failed to start the rabbitmq service. So, I resorted to hostfile entries.
Once you edit the /etc/hosts with the above host file entries also edit the /etc/hostname to include the netbios name at the end (as an extra measure).

Now let us get these VMs ready for Openstack.
setenforce 0
systemctl stop NetworkManager
systemctl disable NetworkManager
systemctl stop firewalld
systemctl disable firewalld

On the controller node
ssh-keygen
ssh-copy-id -i /root/.ssh/id_rsa.pub root@<ip of compute node>
ssh-copy-id -i /root/.ssh/id_rsa.pub root@<ip of neutron node>
we did this to enable ssh to these hosts without having to enter the password everytime. Test the same by doing
ssh root@compute
ssh root@neutron
and they should work.
yum install -y https://www.rdoproject.org/repos/rdo-release.rpm
yum install -y openstack-packstack
packstack --gen-answer-file=/root/answer.txt
now open /root/answer.txt with vi editor by
vi /root/answer.txt
and enter the ip address of the compute and neutron nodes.
Wherever there is an option to set the password (especially for admin and other places) you might want to set a password.
After all this is done just run
packstack --answer-file=/root/answer.txt
 
Notes: 
If for any reason the installation fails with an error complaining about cannot allocated memory, then increase the memory on the controller node to solve it.
Now at the end of the installation you will see an url for the Openstack dashboard. Open it and enjoy.