Usage: netstat [-vwennccf] [<; Af & gt]-r netstat {-V |-version |-h |-help }

netstat[-vWnNcaeol][& lt； Socket & gt...]

netstat {[-vWeenNac]-I |[-cnNe]-M |-s[-6 tuw]}

-r, -route shows the routing table

-i,-interfaces displays the interface table.

-g,-groups shows multicast group membership.

-s,-statistics displays network statistics (such as SNMP).

-M,-Camouflage shows disguised connections

-v, -verbose shows details.

-W,-wide Do not truncate the IP address.

-n, -Numeric does not resolve names.

-numeric-hosts does not resolve host names.

-numeric-ports ignores port names.

-numeric-users ignores user names.

-N,-Symbol Resolution Hardware Name

-e, -extend show more information

-p,-programs displays the PID/ program name of the socket

-o,-timers display timer

-c,-Continuous list

-l,-Monitor display Monitor server socket

-a,-all shows all outlets (default: connected)

-F,-fib displays the forwarding information base (default)

-C,-cache shows the route cache instead of the FIB.

-Z,-context displays the SELinux security context of the socket.

& ltSocket & gt= {-t |-TCP } {-U |-UDP } {-U |-UDP lite } {-S |-SCTP } {-w |-raw }

{-x| - unix} - ax25 - ipx - netrom

& ltAF & gt= Use' -6|-4' or'-a <; "af -& lt；" or'-<; “af & gt”； Default value: inet

List all supported protocols:

Inet (DARPA Internet) inet6 (IPv6) ax25 (AMPR AX.25)

Netrom (AMPR network/rom) IPX (Novell IPX) DDP (AppleTalk DDP)

x25 (CCITT X.25)

It can be seen that -a display all sockets (default: connected) means to display all socket connections without -a, and only the connected socket connections are displayed by default. This is the difference.