Month: January 2014

Ribbon bar is better

Ribbon bar is better. Original design put the major buttons on the LHS, but it grabs space than the tree (describe the openstack architecture). Also the original design put all the function buttons on the bottom, it is better to put it on the ribbon bar that on the top. In ribbon bar, major button will have bigger size than normal button.

Ribbon bar
Ribbon bar

read count : 498

openstack VM hang up after changed screen solution

openstack VM hang up after changed screen solution, i tried to change the screen resolution from 1280×1024 to 800×600, the screen just size down, but the VM is hang. It is completely hang because i can’t even ping/ssh to that VM. Do you know the reason?

vm hang up after changing screen resolution
vm hang up after changing screen resolution

read count : 384

slow ssh connect to host from openstack vm

if you having a slow-login problem when you are trying to connect ssh from the openstack vm to the outside world. This will solve the issue:

Edit /etc/nsswitch.conf , change “hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4” to “hosts: files dns”, no need to restart anything, ssh login prompt will come out quickly.

read count : 503

VM process window, i think this will be good enough

Still working on the VM process window, I want titan user able to see clearly inside VM. In this window, the chart will show the cpu/memory usage of that VM. I will enhance it to:

1. When select a process on the bottom, the chart will show the cpu usage only to that process. This is good, for example you are running a 3d render software, when you click on that render process. You can see which period that process used most of the cpu/mem.
2. I want titan user able to kill process in that window, so user no need to login to that vm to kill any process. This speed up the administration.

VM process window
VM process window

read count : 421

openstack vm can’t access interest (solved)

Here is my home openstack lab, if you follow the openstack official guide┬áto try openstack, your environment will be pretty similar than mine. I met a trouble: my openstack vm can’t access internet. Here is how to solve it:

My environment is:

My home openstack environment
My home openstack environment

1) I got a broadband line, connected to the gateway server, the gateway server got two network cards, one for the broadband and one connected to the switch.

2) the openstack server is connected to the switch and the gateway is set to that gateway server (

3) VMs are running in that openstack server, dhcp and flat network.

Here is how i solve this issue:

We need to forward all the packet come in br100 to the outside world, here are the commands:

iptables --table nat --append POSTROUTING --out-interface  br100  -j MASQUERADE
iptables --append FORWARD --in-interface br100 -j ACCEPT

Something need to be carefully :

  1. do not point your vm’s gateway to your real gateway server, point it to instead
  2. if you restart nova-network, please flush all the iptables rule by “iptables -F” and “iptables -F -t nat”

read count : 1221

Instance chart

You can now select a VM, click the “log” button on the bottom, you can see vm’s cpu/memory chart.

VM chart
VM chart

read count : 275

you can start nova in this way

When you failed to start nova-network or nova-compute by command “service nova-compute start”, the log will has nothing. But you can solve this by “service nova-compute start && ps aux|grep nova-compute”, this command will list out the command line to start nova-compute, just paste that into your terminal, now your nova-compute is running directly rather than using initctl. The log will appear in your terminal, so you can trace the error.

I got an experience that I have a ubuntu server, running with devstack, after I clean it up the devstack by “./” and reinstall the nova by the official guide. I was failed to start nova-network and nova-compute, but if i run the command to start nova directly in console, it runs smoothly.

read count : 221