FingBox doesn't always block

thewoodmaster69 Member Posts: 2
edited December 21, 2020 in Fingbox #1

Sometimes I block some of my kids devices, or the tv and I go down there an hour later and it hadn't been blocked at all, they're still streaming/gaming etc. I have the FingBox plugged directly into the zyxel router. I'll check the app and it shows it's blocked,


  • Robin_from_Fing
    Robin_from_Fing Administrator, Fing Team Posts: 4,761
    250 Answers 2500 Comments 500 Likes 100 Awesomes
    Hi @thewoodmaster69

    The way the Fingbox blocks is through ARP poisoning and DNS Spoofing.  So what is happening is that when you block a single device, the computer DHCP address and DNS entries gets changed and pointed to the Fingbox.  So this device is blocked from getting to the internet or internal resources. 
    For more information on ARP poisoning and DNS Spoofing see the following links: 
    Blocking is done by DNS/Blocking Spoofing. 
    The Fingbox/App work to pause things by a process called ARP poisoning/Blocking. 
    Things that need to be done to make sure that it is going to work are as follows: 
    1. Enable UPnP on your router 
    2. Disable IPv6 on your router (This is required to make sure that Internet Pause and Blocking works) 
    3. Best Practice - Reserve the IP address of the Fingbox 
    4. Create the following TCP rules and point them to the IP address of the Fingbox 

    • 80 (Internet Speed Test) 

    • 443 (Fing Service and Software Updates) 

    • 3001, 3002, 3003 (Internet Speed Test) 

    • 4443 (Fing Service) 

    • 5671 (Fing Diagnostics) 

    One other thing you may want to consider is using Auto-Block as well.  Because Windows 10 and other devices can use MAC randomization.  This means that the MAC address of the computer can change.  Here is a good article on it: 

    Robin (Admin at Fing)
    Getting Started? Please refer to Community guidelines & Community User Guides. HAPPY POSTING!!!