Unable to establish connection to http://controller:35357/v2.0/tenants

If you get this error while using keystone.

Just hash (#) the line start with driver under [token]

#driver = keystone.token.persistence.backends.sql.Token

openstack-install error

If you get the following , when try to run: openstack-install

Error:

Previous installation detected. Did you mean to run openstack-status instead?
If attempting to re-install please run     $ sudo openstack-install -u

you need to delete the following: .cloud-install (under the user home directory)

Enjoy

OpenStack MAAS failed commissioning wakeonlan

If you get the error while try to commission or wake on lan,

you will need to check first if you have it installed on your server (MAAS server).

if you check the template:
/etc/maas/templates/power/ether_wake.template

you will see that it looks for:
/usr/bin/wakeonlan
and
/usr/sbin/etherwake

just install them:
apt-get install etherwake wakeonlan -y

and if you want to test it for each node: i = interface and b = broadcast
/usr/sbin/etherwake -i <INTERFACE> -b <MAC>
/usr/sbin/etherwake -i eth0 -b e8:39:35:39:e3:11

Enjoy,

Chef-client 401 "Unauthorized"

If you get this : Net::HTTPServerException: 401 "Unauthorized"
when running chef-client, you need to verify that you have the fqdn / node name (node_name) in your client configuration.

Chef bootstrap - public key failure

I tried running chef bootstrap using public key on amazon ec2 server, and get some errors:
    ERROR: ArgumentError: invalid option(s): keys_only
Or
   /usr/lib/ruby/1.8/net/ssh.rb:155:in `start': invalid option(s): keys_only (ArgumentError)
well, i don't know if it is a bug, but i create a simple solution for this with a simple script
the following script will allow password, run bootstrap and disallow password

Nagios with graphs installation (step by step)

Did you ever wanted to have alerting system (such as Nagios) and add some graphs

you can find here a short post, with a full description of adding graphs to Nagios

I also add configuration example

EC2 security access when working with ELB

As you know /or not, when working with ELB the security group on the Amazon ec2 instances will not catch the real IP, only the internal ELB ip.

So, how can we prevent this Security hole?