Mikrotik: Change the TTL(Time to Live) on Mikrotik router

Chetta Busayarat

• 3 min read
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Mikrotik: Change the TTL(Time to Live) on Mikrotik router
Photo by Alina Grubnyak / Unsplash


Change TTL (Time to Live) on a mikrotik router for prevent users from share internet from user computer (Share Hotspots, Tethering). Link user mobile phone to share the internet hotspot/tethering.

To prevent this we can set TTL (Time to live) to 1. The packets will expired immediately if they pass throught anoter router.

Time to Live (TTL) is a mechanism that limits the lifespan of data in a computer network or cache to prevent infinite loops, network congestion, or the use of outdated information

When data moves across the internet, it is split into packets. A TTL is a counter or hop limit attached to each packet.

  • How it works: Every time the packet passes through a router (a "hop"), the TTL value drops by 1. If the TTL hits 0, the router discards the packet and sends a notification back to the sender.
  • Why it matters: It prevents packets from endlessly circulating the network due to routing errors.

The concept applies in three primary contexts: In Data Packets (Networking), In DNS Records (Websites), In Caching (Performance).

How to create:

  1. Open Winbox and log-in to your router.
  2. Go to "IP > Firewall > Mangle".

  1. On the mangle tab click "New".

  1. On "Genergal tab" > Chain=postrouting, Dst.Addres= "your subnet",


5. On "Action tab" > Action=change TTL, TTL Action=Change, New TTL=1 > Click OK to create.

  1. Recheck for TTL is changed to 1 as added by using "Packet Sniffer". Open packet sniffer by goto "Tools > Packet Sniffer".

  1. On "General" tab > Click "Start" > then click "Packets" to view.

  1. After click "Packets" the windows "Packet Sniffer" will open.

  1. If the colume not show TTL, Open it by add colum.

  1. Check "TTL" to show.

  1. Now the TTL colume showed and value = 1 (Dst. Address= 172.16.x.x as set on postrouting).

  1. Test change TTL to other value (TTL=2).


13. Back to check the value on "Packet Sniffer".

  1. Using "Filter" view only Dst.Address=172.16.x.0/24 (User subnet).

  1. Another way you can use ping from computer under the user subnet. Ping test and TTL will show.