TCP/IP utility network management command

The ping command is used to send Internet Control Message Protocol (ICMP) packets from one host to another. Ping sends data packets using the icmp echo-REQUEST command, and expects an icmp echo-REQUEST "ping" for each transmitted data packet. The name is from the acoustic detection device (SONAR ), this device uses a similar
Ping the sound waves to determine the target of the surrounding area.

Description of ping options

-C count requires the ping command to send packets continuously until the packets are sent and received count requests

-D: Enable debugging status for the socket used-f is a fast ping method. The ping output packet speed is as fast or faster as the packet returned from the remote host, reaching 100 times per second. In this way, each request is represented by a period. Print a Space key for each response.

-I scconds specifies the number of seconds between two packets. Cannot be the same

-F is used together. -N only uses numbers. In general, ping attempts to convert the IP address to the host name. This option requires ping to print the IP address without looking for the name represented by a symbol. This option is important if you cannot use the local DNS server for some reason.

-P pattern supports the use of this option to identify 16 pad bytes and add these bytes to the data packet. This option is useful when diagnosing data-related errors in the network.

-Q: The ping command only prints some summary information at the start and end.

-R adds the icmp record-ROUTE option to the ECHO_REQUEST data packet and records the ROUTE in the data packet. In this way, when the data is returned, ping the data to print the ROUTE information. Each packet can only record nine route nodes. Many hosts ignore or discard this option.

-R causes the ping command to bypass the normal route table used to send data packets.

-S packetsize allows you to identify the number of bytes of data to be sent. The default value is 56 characters, plus 8 bytes of ICMP data header. A total of 64 ICMP data bytes are added.

-V puts ping in verbose mode. In addition to printing the ECHO-RESPONSE packet, the ping command also prints all other returned ICMP packets.

By default, the finger command lists the current registration name, full name, terminal name, and terminal write status of each user (if you do not have the write permission, there will be a "*" before the terminal)., free time, registration time, office location, and phone number (if any ).

Finger Option

-B: Short output format-f: compress the printing of the first line (short format)

-I provides a quick list of users and idle time

-L forced use of long output format

-P compression. plan file printing-q provides a user's Quick List

-S: force short output format

-W: Use a narrow format to list specified users

The netstat command is used to query subsystems related to certain types of information. Print the route selection table, active connections, streams in use, and other information. Netstat Option

-A displays the addresses of any associated Protocol control blocks. Mainly used for debugging

-A shows the status of all sockets. Generally, the socket-I associated with the server process is not displayed, and the interface status is automatically configured. The Interface States configured after the system initial boot are not in the output Column

-M: Print network memory usage

-N: print the actual address, instead of explaining the address or displaying symbols such as host and network name.

-R print route selection table

-F address

-Family prints statistics and control block information for address clusters with names. So far, the only supported address cluster is inet.

-I interface: only the interface status with the given name is printed.

-P protocol

-Name: only the Protocol statistics and Protocol control block information with the given name are printed.

-S: print the statistics for each protocol

-T replaces the queue length information with time information in the output display.

Column Title of the netstat command

Column description

Name of the interface

Maximum Transmission Unit of the Mtu Interface

Net/Dest Interface Network

Number of packets received by Ipkts

Number of corrupted packets received by Ierrs

Number of packets sent by Opkts

Number of corrupted data packets sent by Oeers

Collisions number of network conflicts recorded by this interface

TCP socket explanation status meaning

CLOSED does not use this socket

LISTEN socket is listening for inbound connection

SYN_SENT socket is trying to establish a connection

SYN_RECEIVED is in the initial synchronization state of the connection.

The ESTABLISHED connection has been ESTABLISHED.

CLOSE_WAIT remote socket closed: waiting to close this socket

The FIN_WAIT_1 socket is closed and the connection is being closed.

The CLOSING socket is closed, the remote socket is closed, and the close confirmation is temporarily suspended.

LAST_ACK remote socket already exists, waiting for confirmation of local socket close

FIN_WAIT_2 socket closed, waiting for remote socket to close

TIME_WAIT the socket has been closed, waiting for the remote socket to close Transfer

Traceroute/tracert command

The traceroute/tracert command is used to track the route of a data packet to the target machine, and uses the time-to-live (TTL) domain of the IP data packet, each gateway that passes the packet before it reaches the remote host triggers an ICMP TIME_EXCEEDED response.

Arp command

The arp command displays and modifies the address translation table from Internet to Ethernet. This table is generally maintained by the address translation protocol (ARP. When only one host name is used as the parameter, arp displays the current ARP entry for this host. If the host is not in the current ARP table, ARP displays a description.

Option description

-A: List all entries in the current ARP table.

-D host: Delete the corresponding entry of a host from the ARP table

-S host address uses the ethernet address to create an entry for the specified [temp] [pub] [trail] host in the ARP table. If the keyword [temp] is contained, the created entry is temporary; otherwise, the entry is permanent. [Pub] The ARP entry identified by the keyword will be published. Use the [trail] keyword to indicate that tail encapsulation will be used

-F file: reads a file with a given name and creates an ARP table entry based on the host name in the file.
Publisher: beyond
Source: Excerpt