icmp - TTL Exceeded mpls

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Hello, colleagues. Help to solve following problem :
There is a diagram of switching on

Customers ->MX240--ldp lsp-->X670--ldp lsp-->X670--ldp lsp-->ldp lsp-->X670--ldp lsp-->MX480-->Internet

All Extreme X670  - 15.7.2.9 - intermediate LSR
MX240 - egress mpls lsr
MX480 - ingress mpls lsr

Between MX240 and MX480 bgp session is set .
Сustomer does traceroute :

traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 60 byte packets
 1  10.10.10.1 (10.10.10.1)  0.327 ms  0.332 ms  0.315 ms
 2  * * *      here shall be first X670
 3  * * *      here shall be second X670
 4  * * *      here shall be third X670

To documentation it is written :
 "In pipe TTL mode, the LSP is viewed as a point-to-point
link between the ingress LSR and the egress LSR; intermediate LSRs
in the MPLS network are not viewed as router hops from an IP TTL
perspective. "


Why from X670 doesn't come ttl exceeded ? Why X670 generally is visible in trace ?
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Vladimir Shencov

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Posted 3 years ago

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andreas

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Do you mean that the trace dosen't show the X670 ?
 

// Andrease 
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Vladimir Shencov

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Yes.
 I supposed that X670 generally won't be visible in the route
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andreas

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Yeah since juniper use two different styles of this I'm not sure that extreme even support this ? cause it has to happen at the LSP level. 

// Andeas
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Vladimir Shencov

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Analogs  mpls icmp-tunneling , mpls no-decrement-ttl on X670 I didn't find .
From hopelessness I tried iproute mpls-next-hop, ospf mpls-next-hop , but it of course didn't help.