Goal

How

We should build a CentOS 6 / SLC6 image that is remastered and contains a chef-client RPM + chef-configuration-fetcher script, to get our specific configuration, after this, chef will do the rest.

• Once the Kickstart image is done, we should use it in the usual kickstart
  • Take the care here, to be able to push the button for worker nodes, they will be back online, by kickstarting, because in principle, all the information there is transient, except, if we can keep HDFS data partition + metadata
  • I (samir) don't want this happening for servers yet (CE,SE, GFTP)
• DHCP -- we will need to keep a table of MAC/Hostname/IP address, specially find a way to tell KS if the node should be reinstalled or not, switcheable flag.
• Forget everything, seems that Cobbler just does the job

Useful tutorials :

• DHCP+BOOTP - to define the kickstart via PXE - for SLC6, sed 's/lib/share/g'

Chef client

Official CentOS 6 way to install is still too much manual and has to be scripted, we really want an RPM for that, it seems that the biggest difficulty is that they "wget" the gems, and want to install for source, instead of putting a simple RPM dependency, drawback is that you start to go off the RPM track, which we want to keep.

Official Tutorial here

• Bad news : Official support is not to RPMs.
  • Not really, check the Omnibus installer
  • Not really (2) , you can download RPMs for the specific version you want here, so you make sure of the release, and also that you don't need external connection to operate
• Good news : Once chef client is installed properly, we "just" need to fetch the generic configuration file (webserver,NFS), put it in the right place, restart the service.