Why can't I access TNAS after setting up a firewall?

[TMzethar]

troubleshooting

Applicable models
All TNAS models

Applicable system
All TOS versions

Fault phenomenon
When creating rules in TOS > Control Panel > Security > Firewall, the computer currently used to access TOS is also blocked by the firewall due to misoperation or insufficient or wrong understanding of firewall rules.misoperation or insufficient understanding of firewall rules.

Cause Analysis
According to user feedback and our repeated verification, we have concluded the following reasons.
On the one hand, we have been missing the necessary instructions for the firewall. TOS's firewall is implemented through the Linux iptables command line, and the complex command line is simplified into the firewall UI you see. The "allow" rule is actually "allow only", which is where some users get it wrong. We have plans to add descriptions to help more users.
On the other hand, some users have inherited part of the usage habits of Windows Firewall to TOS Firewall. When setting up services or applications that need to open ports, users may think that TOS does not open certain ports to certain IP addresses, so they set a rule of "allow" certain protocols on certain ports of certain IP addresses, resulting in All remaining IP addresses, ports and protocols are inaccessible. In fact, Linux's iptables is enabled by default, but there are no rules by default, allowing all network traffic to pass.

Solution
1. If you only create a rule to "allow" a certain IP address or a certain IP address range, you can directly connect your TNAS to the computer, and then configure the network card of your computer as a certain "allow" IP address. Then you can access TOS and reconfigure.

2. If you created a rule to "allow" a certain port or port range, or a rule to allow a certain protocol, or you have even forgotten the rules, please reset the configuration by reinstalling the TOS:viewtopic.php?f=76&t=423