This reports whether the card's IP routing table is within its configured size limit, normal, or has exceeded it, marginal, in which case per its own description every route except management prefixes gets discarded. A marginal(2) reading here is a serious, specific outage signal: it means real customer or transit routes on this card have actually been dropped from the table to protect memory, keeping only management traffic reachable, so this needs immediate attention rather than being treated like an ordinary capacity warning. For example, cardIPTableState flipping to marginal(2) after a route-leak event explains why customer traffic through this card suddenly stopped routing while the card itself remained reachable for management.