What Do Such BGP Peer States As Active, No neg, and Idle (Admin) Stand For?

In addition to Idle and Established, the BGP peer has the following states:

• Active: indicates that the TCP connection of the BGP session is not established.
• No neg: indicates that the capability of establishing the BGP connection is not negotiated. The IPv4 unicast is configured on one end, whereas the IPv4 unicast and IPv4 multicast are configured on the other end. After the neighbor is set up, you find that the IPv4 unicast is adopted through the negotiation and it is in the Established state, whereas the IPv4 multicast is in the No neg state because the IPv4 multicast is not configured on one end.
• Idle (Admin): indicates that the neighbor relationship is shut down initiatively and no attempt is made to establish the neighbor relationship. If the peer ignore command is configured or the peer is set to the Down state through the MIB, the neighbor is in the Idle (Admin) state.