If the linux you are asking uses TCP/IP specification, and the port range is 0-65535, in which all zeros are meaningless, then you can use port 1-65535.

How does linux open the port?

Nc-lp22 (requires root permission, if you are not logged in as root, you can use suroot or sudo to declare permission). When finished, you can use the change command to query whether netstat-an|grep22 has been opened.

What is the terminal port of linux?

The default is port 22, which is the service port of sshserver.

What instructions does linux use to create local ports and IP?

Linux system uses command netconfig to create local port and IP address.

What is the iscsi port under linux?

Just check it through /etc/services:

#grep-iiscsi/etc/services

iscsi860/tcp#iSCSI

iscsi860/udp#iSCSI

iscsi-target3260/tcp#iSCSIport

iscsi-target3260/udp#iSCSIport