Edison compute nodes run a stripped down Linux operating system called Compute Node Linux (CNL). Some standard Linux services, such as ssh, rsh, nscd, and ldap, are not supported on the compute nodes. As a result, some user applications can not run in Edison's native enviornment. Cluster Compatibility Mode (CCM) is the Cray software solution to this problem. It provides the standard Linux services needed to run most cluster-based independent software vendor (ISV) applications on Cray machines. Under CCM, everything an application "sees" is a standard Linux cluster. CCM is made availble on Edison to accommodate workflows that need standard Linux services. Codes such as G09, Wien2k, Matlab, and other ISV applications can run under CCM.