MPLS TE CSPF

Dear
NIE fellows,

I'm
pretty new to the MPLS TE topic, and I've a question for which I can't find an answer
on my readings

 

image

 

let's  assume that we have the topology in the attached diagram

 

IS-IS is
used as the IGP; with MP-BGP for VPN traffic, PE to CE is eBGP

Every
link is a 10 Mbps link of which 6 Mbps are used by TE,

every
node has a master tunnel which has   a default tunnel and an LLQ tunnel

the
TE metric has been left by the default (equal to the IGP metric)

every
single  node has tunnel to all other
nodes (full mesh tunnels)

all
tunnel interfaces have the config bellow 

interface
Tunnel10

 description Tu RX (Master)

 bandwidth 10000

 ip unnumbered Loopback0

 tunnel mode mpls traffic-eng

 tunnel destination 169.254.1.2

 tunnel mpls traffic-eng autoroute announce

 tunnel mpls traffic-eng exp-bundle master

 tunnel mpls traffic-eng exp-bundle member
Tunnel11

 tunnel mpls traffic-eng exp-bundle member
Tunnel12

!

interface
Tunnel11

 description Tu Rx (Default)

 bandwidth 6000

 ip unnumbered Loopback0

 load-interval 60

 tunnel mode mpls traffic-eng

 tunnel destination 169.254.1.2

 tunnel mpls traffic-eng autoroute announce

 tunnel mpls traffic-eng priority 7 7

 tunnel mpls traffic-eng bandwidth 4000

 tunnel mpls traffic-eng path-option 10 dynamic

 tunnel mpls traffic-eng record-route

 tunnel mpls traffic-eng fast-reroute

 tunnel mpls traffic-eng auto-bw frequency 300
adjustment-threshold 5 max-bw 4000 min-bw 1000

 tunnel mpls traffic-eng exp default

!

interface
Tunnel12

 description Tu RX (LLQ)

 bandwidth 4000

 ip unnumbered Loopback0

 tunnel mode mpls traffic-eng

 tunnel destination 169.254.1.2

 tunnel mpls traffic-eng autoroute announce

 tunnel mpls traffic-eng priority 7 7

 tunnel mpls traffic-eng bandwidth sub-pool
2000

 tunnel mpls traffic-eng path-option 10 dynamic

 tunnel mpls traffic-eng record-route

 tunnel mpls traffic-eng fast-reroute

 tunnel mpls traffic-eng exp 5

 

 

My
Questions are

1-     Having the
default  MPLS TE metric equal to the IGP
metric , and assuming that the path going to R9 through R8 is always the best
path from an IGP point of view

the
LSP being used to get from R1 to R9 is R1-R8-R9 and  all reservable bandwidth has been used (6
Mbps) , so we have 4 Mbps left on R8-R9

R2-R8-R9
is the best path (best Metric IGP/TE)

When
RSVP signals the LSP to go to from R2 to R9 is the LSP going to be built using
a less preferred path in terms of metric or will this result in and admission
control failure?

 

2-     Is the
sub-pool bandwidth dedicated from  the
master tunnel interface or the Tunnel 12 ?

 

Many thanks in advance for your help

Kind regards

Mehdi

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