Why does it give a high TTL when pinging?

Question

network hardware

In the normal state, the router (TPLINK) pings with 64 TTL, the network works without problems.
At some points in time, the ping gives TTL 254, the ping time does not increase, the grid drops, there is no Internet. Until the device is rebooted. Ping to other devices is normal

Answer 1

Sometimes such TTL appears when the device is switched to Recovery mode.
If the router does this on its own, then it is better to update the firmware to the latest version, reset to default settings and configure again.
Or connect to the console port on the router board and directly view the logs at the time of transition to this state.

Answer 2

TTL is the "time" (in quotes - because not in seconds, but in transitions) of the life of the packet. how many routers can it go through before it "dies".
the field is 8-bit, so the maximum TTL = 255. A large ttl should not affect the network's performance in any way - the packet will die anyway when it reaches its destination. Standard TTL = 64.
TTL change is most likely caused by pinging from different devices/OS.

Answer 3

each router adds ttl so that the packet is not lost. In my opinion, both l2tp and nat add ttl.