The default sftp port number for linux is 22.

At the same time, if you modify the port number of other sftp servers, you can use -P to specify which port number to connect through.

For example, XFtp uses sftp, the default port of sftp is 22, and the actual sftp uses the port of sshd process (port 22).

The difference between ftp port number 20 and 2 1 is that one is a data port and the other is a control port. The control port is generally 2 1, but the data port is not necessarily 20, which is related to the application mode of FTP. If it is active mode, it should be 20. If it is passive mode, it is decided by the server and the client through negotiation.

What are the commands of linux open port?

First, check which ports netstat-anp has opened. Second, close the port number: iptables-a input-ptcp-drop port number -jdropptitables-aoutput-ptcp-dport port number-jdrop. Third, open the port number: iptables-a input-ptcp-dport port number -jACCEPT. Four, the following is the use of linux open port command. Nc-lp23 (open port 23, telnet)netstat-an|grep23 (check whether to open port 23) V. linux open port command Each open port needs a corresponding listener.

What if the server port of linux server is locked?

First terminate the process that caused the port to be locked, and then restart the port.

What is the application corresponding to linux54 port?

Familiar with port number: 0~ 1023. Each port is suitable for a specific application protocol.

Dynamic port number: 1024~65535 The client is assigned to each application process.

tcp(6):

FTP data (20)

FTP control (2 1)

Remote login (23)

Simple Mail Transfer Protocol SMTP(25)

HTTP(80)

POP3 (Electronic post office protocol) (1 1

UDP( 17)

Simple file transfer protocol TFTP(69)

Simple Network Management Protocol SNMP( 16 1)

DNS Domain Name System (80)-It is both tcp and udp.

In linux, how to check which files are used by a process? What network port do you use?

View only the process: ps-ef|grep 1 1345 View the files opened by the process: lsof-p 1 1345 View the memory allocation: lcat/proc/1kloc-0/345/maps.