Unsupported Features

E-series routers do not currently support the following route tag features:

Multiple route tags for a single IS-IS route
Although the router accepts IS-IS routes with multiple route tags and propagates these routes in LSPs, it uses only the first route tag assigned to a route to determine routing policy.
64-bit (8-octet) route tags
Although the router accepts IS-IS routes with 64-bit route tags and propagates these routes in LSPs, it does not use 64-bit route tags to determine routing policy.
Mathematical (ordered) set operations on multiple route tags