OID value: 1.3.6.1.2.1.6.6
OID description:
tcpPassiveOpens OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "The number of times TCP connections have made a direct transition to the SYN-RCVD state from the LISTEN state." ::= { tcp 6 }
See also the OID Repository website reference for 1.3.6.1.2.1.6.6