Torgeek
- How to block port 22 in Linux?
- Can I block port 25?
- Can port 80 be blocked?
- How to disable port 443 in Linux?
- Should I block port 80 and 443?
- Can I block port 443?
How to block port 22 in Linux?
Disable TCP/22 by commenting it out in the sshd_config file. Disable TCP/22 by modifying /etc/services so that the only open SSH port is TCP/33001. In OpenSSH versions 4.4 and later, disable SSH tunneling to avoid potential attacks by adding the following lines at the end of the sshd_config file.
Can I block port 25?
An ISP (Internet Service Provider) may block port 25 in order to prevent spamming by its customers. With port 25 being blocked, you won't be able to host your own mail server at home or work.
Can port 80 be blocked?
Some (mostly residential) ISPs block port 80 for various reasons. If your ISP does this but you'd still like to get certificates from Let's Encrypt, you have two options: You can use DNS-01 challenges or you can use one of the clients that supports TLS-ALPN-01 challenges (on port 443).
How to disable port 443 in Linux?
Solution: There is a file in "\apache\conf\extra" called http-ssl. conf that had a command saying "Listen 443" (line 20). Just change it, delete it, or add a # before it to solve the issue. How do you know it currently listens to 443?
Should I block port 80 and 443?
We occasionally get reports from people who have trouble using the HTTP-01 challenge type because they've firewalled off port 80 to their web server. Our recommendation is that all servers meant for general web use should offer both HTTP on port 80 and HTTPS on port 443.
Can I block port 443?
As the URL Redirection feature only works for supported browsers, an Application Control Network Connection rule can be used to block access e.g. *. 80 and *:443. After configuring a Network Connection hostname rule, web browsers such as Chrome may still be able to access the web site over HTTPS.
