Dan Carley dcarley

Using strace and lsof to debug blocked processes

You can use strace on a specific pid to figure out what a specific process is doing, e.g.:

strace -fp <pid>

You might see something like:

select(9, [3 5 8], [], [], {0, 999999}) = 0 (Timeout)

	#!/usr/bin/env ruby
	# strawman - a simple puppet template checker.
	# use like:
	# echo 'fqdn => test.example.org\n$webserver = ["host1", "host2"]' \| strawman template.erb
	# where fqdn is in facter format:
	# key => value
	# and $webserver is a global ruby var, like in your manifests
	# seperated by newlines, delivered on STDIN
	require 'erb'

	Name : rabbitmq-server-plugins
	Version : 2.6.1
	Release : 1
	Summary : Plugins for RabbitMQ server
	Group : Development/Libraries

	Source0 : http://www.rabbitmq.com/releases/plugins/v%{version}/amqp_client-%{version}.ez
	Source1 : http://www.rabbitmq.com/releases/plugins/v%{version}/rabbitmq_stomp-%{version}.ez
	Source2 : http://www.rabbitmq.com/releases/plugins/v%{version}/rabbitmq_management_agent-%{version}.ez
	Source3 : http://www.rabbitmq.com/releases/plugins/v%{version}/rabbitmq_management-%{version}.jquery-fix.ez

	require 'base64'
	require 'digest/md5'

	key = "your public key here"

	# first decode the key
	key_decoded = Base64.decode64(key)
	# create an md5
	md5 = Digest::MD5.hexdigest(key_decoded)
	# convert that hash into a readable fingerprint