Tks, but I think I failed to describe my problem clearly.
I know how to set sshd to listen at different port other than 22.
but after I set my sshd to listen at, say, 2222 port. I need to know how to use sftp connect to this server from another linux box in command line.
I know how to connect via ssh:
ssh 18.104.22.168 -p 2222
but how to use sftp?
man sftp said used -oPort=2222 but doesnt work. sftp still said failed to connect to port 22