Saturday, August 31, 2013

Configuring CENTOS 6.4 minimal install for Wireless without NetworkManager using WPA_Supplicant

I found myself configuring a lot of CentOS based devices as nodes for my lab environment. Sometimes it is easier to connect them wirelessly than having a bunch of cables around. Since I use this nodes with CentOS 6.4 minimal install, getting the wireless to be the primary uplink interface requires a series of steps.

First we need to install the wireless tools and other tools that we need for wireless encryption configuration and so on. So, the first step is this:

yum install wireless-tools wpa_supplicant dbus

BIND/named with PostgreSQL back end at CentOS 6.4

I've been trying to find a good documentation on setting up Bind with PostgreSQL as its back end. So far the information is sparse so I've decided to put this recipe together. There is much more than this but the idea is to give you a start.

1) First, make sure you have bind, bind-sdb, postgresql-server RPMs (and their dependencies) installed.

2) After having the RPMs in your system, you have to configure the iptables to allow DNS queries. Edit /etc/sysconfig/iptables to allow queries to the DNS port. Include the following statement after the SSH entry:

-A INPUT -m state --state NEW -m udp -p udp --dport 53 -j ACCEPT

Make sure you reload your iptables for this change to get the new rules into effect.

Monday, May 30, 2011

Reflection: Will managed hosting providers run out of capacity?

Today I came across a post which made me reflect for a moment: Will managed hosting providers run out of capacity by 2012?

My "extended" reflection:

My first reaction was "interesting question". I saw it can be looked from various angles.  Will they "run out of capacity"? Capacity of what or for what?
  • Network capacity? Traffic demand has been growing exponentially. I believe that eventually we may reach a point were we will not be able to build infrastructure (i.e. fiber) as fast as it is needed. When everything start migrating to "the cloud" and hyper connectivity become a wide social demand, that will be the moment. What will happen when this hyper connectivity status spread out to the "major cities"? What if that request happen in relative short time frame? Imagine if that in 10yrs from now the world get out of the recession to a hyper connected world wide boom era?
  • Storage capacity? We are already generating huge amount of data per minute. Can you think how much will it be in the next decade? 
    • Last year (Aug 2010) Eric Schmidt said that every two days we create as much information as we did from the dawn of civilization up until 2003. How much we will be generating in 5 years? We will have enough primary materials to build the storage or space to put it?
  • Capacity to find adequate human resources? With the new generations more interested in games than understanding technology or even studying I think we can run out of human resources during the next decade unless governments take action. (or probably we will have nations that will become the source of outsourced services) 
  • Power capacity? We already have problems supplying our current demands. What about in 10 years? 

So, going back to the original question "for 2012"? I don't think so.  But we need major shift in current hardware and communication infrastructure to be able to handle it.