How do disabling MPLS TTL propagation?

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How do disabling MPLS TTL propagation?

  The IP header includes a TTL field and MPLS labels also have a TTL field.  
At every routed hop than TTL is decremented by one.
If the reaches zero before the packet is discarded then ICMP TTL exceeds a message is sent to its source.

  MPLS routers copy the TTL of an IP packet when it enters the LSP,
such that an IP packet receives an MPLS label TTL values.
So routers decrement the MPLS TTL in place of the IP TTL at every label-switched hop.

  Cisco calls behavior this TTL propagation and you can
disable MPLS TTL propagation. You can use the command no mpls ip propagate-ttl under global config.
If you only influence originates outside, you should be applied to PE router in the MPLS domain.

Now MPLS TTL is calculated independent of the IP TTL,
and the IP TTL remains constant for the length of the LSP.
then these MPLS hops are not recorded in the traceroute.