How to free up port 22 on Google Compute Engine - google-cloud-platform

Question

In Google Compute Engine, I would like to use port 22 for SFTP although I cannot since the VM says that there is sshd running on this port. Is there any way I can change the port sshd uses to a different one so I can free up 22?
I tried to look at: How to change sshd port on google cloud instance?, but it did not help and the port for sshd was still 22 after I executed:
sudo netstat -pna | grep 22
The output is:
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 53151/sshd
tcp6 0 0 :::22 :::* LISTEN 53151/sshd
Thank you for your time!

Answer 1

You can change the SSH port 22 as per below steps:
Log on to the server as an root user
Open the SSH configuration file sshd_config with the text editor vi: vi /etc/ssh/sshd_config.
Search for the entry Port 22.
Replace port 22 with a port between 1024 and 65536.
semanage port -a -t ssh_port_t -p tcp New-SSH-Port
semanage port -l | grep ssh
ssh_port_t tcp 2222, 22
systemctl restart sshd
netstat -pna | grep 2222
tcp 0 0 0.0.0.0:2222 0.0.0.0:* LISTEN 1525/sshd
tcp 0 0 10.128.0.33:2222 35.235.241.19:63372 ESTABLISHED 1413/sshd: mdmahboo
tcp6 0 0 :::2222 :::* LISTEN 1525/sshd
systemctl status sshd
● sshd.service - OpenSSH server daemon
Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled)
Active: active (running) since Sun 2021-02-21 02:46:55 UTC; 46s ago
Docs: man:sshd(8)
man:sshd_config(5)
Main PID: 1525 (sshd)
CGroup: /system.slice/sshd.service
└─1525 /usr/sbin/sshd -D
Feb 21 02:46:55 cenos-1 systemd[1]: Stopped OpenSSH server daemon.
Feb 21 02:46:55 cenos-1 systemd[1]: Starting OpenSSH server daemon...
Feb 21 02:46:55 cenos-1 sshd[1525]: Server listening on 0.0.0.0 port 2222.
Feb 21 02:46:55 cenos-1 sshd[1525]: Server listening on :: port 2222.
Feb 21 02:46:55 cenos-1 systemd[1]: Started OpenSSH server daemon.
Add firewall entry for port 2222 in GCP firewall
Now, you will be able to login to the VM using your custom port number after allowing the port as ingress in firewall rule.