#no mpls ip propagate-ttl cmd question-?

Question

Hi:
When this cmd. is enabled both on PE1 and PE2 across a MPLS core, why does the trace output show the egress PE2 router in the output?
I have CE1->PE1->P->PE2->CE2.
I am tracing to the lo0 of CE2 10.1.8.8
PE1#conf t
Enter configuration commands, one per line. End with CNTL/Z.
PE1(config)#no mpls ip propagate-ttl
PE1(config)#end
PE2#conf t
Enter configuration commands, one per line. End with CNTL/Z.
PE2(config)#no mpls ip propagate-ttl
PE2(config)#end
CE1#tr ip 10.1.8.8
Type escape sequence to abort.
Tracing the route to 10.1.8.8
1 10.1.17.1 28 msec 28 msec 28 msec
2 10.1.58.5 168 msec 180 msec 168 msec
3 10.1.58.8 112 msec * 112 msec
CE1#
As you can see, 10.1.58.5 is the PE2 intf. to CE2. I was hoping to see only 2 hops.
Now the doc for this cmd does say that it sometimes shows the egress provider router.
Is this based on IOS or router model?
Or just another bug ;->
Thx.

Answer 1

Thanks Harold!!
I was going by the example shown in the pdf for MPLS Technology Essentials where they only showed 2 hops, the 1st PE and then CE2 and thus....(they did state that sometimes the egress PE would also show up)....