Bash scripting 24 – firewalls

I am still experimenting with gopher, however this got me thinking about system security, so I have installed.

If you are not sure what you are doing with this, please consult the man page

man ufw

So this describes ufw as

ufw - program for managing a netfilter firewall

As I am ssh'd in to the pi, then the firewall needs to be enabled, however, first make sure that that port 22 (or which ever port you are using for ssh) is allowed. I have to do this as being logged in via ssh, emabling the firewall could block ssh preventing access.

sudo ufw allow 22

Then check the status

sudo ufw status
Status: active

To                         Action      From
--                         ------      ----
22                         ALLOW       Anywhere                  
22 (v6)                  ALLOW       Anywhere (v6)             

To confirm that port 22 is allowed, then enable

sudo ufw enable

Links

• using UFW
• Port Numbers
• Wikipedia TCP
• Wikipedia UDP

Tags

#Bash,#Bashscripting,#BashScripting#Security,#Firewall

CyberSecurity part 15

As this series is going to eventually get to looking at cybersecurity, it would be a good idea to learn about networking concepts. This video seems good at explaining some of this. In fact, it also covers firewalls, which I had planned for a later post.

• Networking basics (2020)

I have also added links to details of common network ports and their associated services.

What is:

• a switch
• router
• gateway
• subnet
• gateway
• firewall
• DMZ

Links

• virtual machine login link
• Common Network Ports

Tags

#CyberSecurity,#Networking,#Ports,#Switch,#Subnet,#IP,'#Gateway,#Firewall,#DMZ,#Router,#Ports