def update_pkgs_filtered(roles, excludes, maxiterations = 16, iteration = 1, blocks = []):
	print "Installing packages with filtered blocks"
	packages = os.popen("/usr/bin/yum %s -y groupinfo %s" % (excludes, roles)).readlines()
	packages = [package.strip() for package in packages if package.startswith("   ")]
	exclude_file = open("/etc/excludepkg", "r")
	excludelist = ["--exclude %s" % exclude.strip() for exclude in exclude_file]
	excludes = " ".join(excludelist)
	errored = False
	(input, output) = os.popen4("/usr/bin/yum -y %s install %s" % (excludes, " ".join(packages)))
	for line in output.readlines():
		if line.startswith("Error: Missing Dependency: ") or line.endswith(" is not signed"):
			errored = True
	if not errored:
		update_log()
		return
	else:
		if iteration == maxiterations:
			raise Exception
		blocks.extend([line.split()[-1] for line in output.readlines() if line.startswith("Error: Missing Dependency: ")])
		blocks.extend([line.split(".", 1)[0].split("-", 1)[-1].split()[1] for line in output.readlines() if line.endswith(" is not signed")])
		blocks = list(set(blocks))  # remove duplicates
		return update_pkgs_filtered(roles, excludes, maxiterations, iteration + 1, blocks)