A Quick and Neat :) Orchestrator using GNU Parallel

Sometimes you have to deal with servers that you don’t know anything about:

  • You are a short temp IT consultant with not previous knowledge on the environment.
  • The CMDB is out of order.
  • You are on a DR situation.
  • Or simply the main administrator is not there.

And you need:

  • Run commands in parallel
  • Get info from many servers at a time
  • Troubleshoot DNS problems
  • Check how many servers are up and running

On my systems I use two orchestrators: MCollective and SaltStack (configured automatically using puppet) that fulfill my needs. But let’s see a quick way to have an orchestrator in a rapid manner.

Continue reading


How to configure the Comtrend’s HG532c ADSL router ARP table for (WOL) Wake On Lan from internet using expect

Several months ago I finally got the (WOL) Wake On Lan feature of my RTL8111/8168B NIC card working. The problem was that a new driver (other than the provided by Debian) and a special PCI configuration was needed.

The other problem I had to deal with was the ADSL Router (Comtrend HG532c, The one provided by the Spanish ISP Jazztel) configuration:

  • Open the required port: This was an easy one just opening the 7 a 9 port and forwarding them to the server we want to WOL from the internet
  • Make the router remember the server’s tuple MAC/IP address. That was easy too, but some manual work was needed as when router is restarted the ARP table is flushed.  :(

In my current job I had to change recently some configuration and restart more than 600 IP phones. To perform such titanic task I created a quick and dirty script using expect. It worked like a charm and made me think about automatize the way I set the ARP table in my Comtrend HG532c ADSL router.

Continue reading