Each line in the node labels file consists of an identifier (a regular expression that identifies one or more nodes), whitespace to separate the identifier from the labels, then one or more labels (separated by commas, whitespace, or both) to apply to the specified nodes. If a label contains two or more words (such as "High Memory"), enclose the name in single or double quotation marks so the whitespace will not be interpreted as a delimiter between two labels.
<identifier>
<label1>[,<label2>,...,<labeln>]
Labels must not start with a digit.
The identifier specifies nodes by matching the node names or IP addresses in one of two ways:
Unix-style glob which supports the ? and * wildcards
Java regular expressions (refer to http://docs.oracle.com/javase/6/docs/api/java/util/regex/Pattern.html for more information)
The identifier must match the fully qualified domain
name (FQDN). To determine the FQDN, run the command hostname
--fqdn.