About Adam Young

Once upon a time I was an Army Officer, but that was long ago. Now I work as a Software Engineer. I climb rocks, play saxophone, and spend way too much time in front of a computer.

Signed Authentication and Authorization

Openstack Keystone currently operates on-line validation for Tokens.  Once a token is issued out,  each of the systems presented with the token has to check the validity of the token with the Keystone server.  This makes Keystone the highest traffic service in an Openstack deployment.  Using Cryptographic Message Syntax (CMS) we can generated a token that can be verified using public key cryptography instead of making a network call.  Here’s a proof-of-concept example using the command line tools.

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Setting up SSL with NSS is easier than you think

At least, it is on Fedora 16

sudo yum install mod_nss

/etc/httpd/alias/ is populated already with ca and server cert self signed
/etc/httpd/conf.d/nss.conf already exists
change 8443 to 443 in two places

--- /etc/httpd/conf.d/nss.conf.orig	2012-03-29 12:59:06.319470425 -0400
+++ /etc/httpd/conf.d/nss.conf	2012-03-29 12:19:38.862721465 -0400
@@ -17,7 +17,7 @@
 # Note: Configurations that use IPv6 but not IPv4-mapped addresses need two
 #       Listen directives: "Listen [::]:8443" and "Listen 0.0.0.0:443"
 #
-Listen 8443
+Listen 443
 
 ##
 ##  SSL Global Context
@@ -81,7 +81,7 @@
 ## SSL Virtual Host Context
 ##
 
-
+
 
 #   General setup for the virtual host
 #DocumentRoot "/etc/httpd/htdocs"

Make sure your firewall is open on the HTTPS port. Add the following line in /etc/sysconfig/iptables

-A INPUT -m state --state NEW -m tcp -p tcp --dport 443 -j ACCEPT

before the statement

-A INPUT -j REJECT --reject-with icmp-host-prohibited

and restart the services

sudo systemctl restart iptables.service
sudo systemctl restart httpd.service

The documentation provides a lot more detail. Almost all of these steps are performed by the RPM install on F16 and later.

Shared Nothing Diskless Boot

It is possible to run a computer with no persistent storage for its root file system other than a single image downloaded an held in RAM. The computer does not needs a local disk. The computer also does not need a SAN or NAS device for the Root File system.

There are numerous uses for this style of booting. A short list:

  • Debugging the installation processes of software packages
  • Running computationally intensive tasks on a large array of nodes
  • Inventorying the hardware on new servers
  • Deploying a light management framework for virtualization hypervisors
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