TE tunnel with dynamic path

[olorunloba]

I configured an MPLS TE tunnel, it stays down, giving the following error

R4#sh mpls traffic-eng tunnels tun 0

Name: R4_t0 (Tunnel0) Destination: 100.1.44.1

Status:

Admin: up Oper: down Path: not valid Signalling: Down

path option 1, type dynamic

Config Parameters:

Bandwidth: 500 kbps (Global) Priority: 0 0 Affinity: 0x0/0xFFFF

Metric Type: TE (default)

AutoRoute: disabled LockDown: disabled Loadshare: 500 bw-based

auto-bw: disabled

Shortest Unconstrained Path Info:

Path Weight: 1562 (TE)

Explicit Route: 100.1.77.5 100.1.77.1 100.1.44.1

History:

Tunnel:

Time since created: 16 minutes, 46 seconds

Time since path change: 13 seconds

Prior LSP:

ID: path option 1 [32]

Removal Trigger: path option updated

Last Error: PCALC:: No path to destination, 100.1.44.11

R4#

When I change to a specific explicit path, it comes up

R4#sh mpls traffic-eng tunnels tun 0

Name: R4_t0 (Tunnel0) Destination: 100.1.44.1

Status:

Admin: up Oper: up Path: valid Signalling: connected

path option 1, type explicit test (Basis for Setup, path weight 1562)

Config Parameters:

Bandwidth: 500 kbps (Global) Priority: 0 0 Affinity: 0x0/0xFFFF

Metric Type: TE (default)

AutoRoute: disabled LockDown: disabled Loadshare: 500 bw-based

auto-bw: disabled

InLabel : -

OutLabel : Serial0/0.2, 17

RSVP Signalling Info:

Src 100.1.44.4, Dst 100.1.44.1, Tun_Id 0, Tun_Instance 39

RSVP Path Info:

My Address: 100.1.44.4

Explicit Route: 100.1.77.5 100.1.77.1 100.1.44.1

Record Route: NONE

Tspec: ave rate=500 kbits, burst=1000 bytes, peak rate=500 kbits

RSVP Resv Info:

Record Route: NONE

Fspec: ave rate=500 kbits, burst=1000 bytes, peak rate=500 kbits

Shortest Unconstrained Path Info:

Path Weight: 1562 (TE)

Explicit Route: 100.1.77.5 100.1.77.1 100.1.44.1

History:

Tunnel:

Time since created: 18 minutes, 4 seconds

Time since path change: 7 seconds

Current LSP:

Uptime: 7 seconds

Prior LSP:

ID: path option 1 [32]

Removal Trigger: path option updated

R4#

Find below the config of the tunnel. Is there something I'm doing wrong?

interface Tunnel0

ip unnumbered Loopback0

tunnel destination 100.1.44.1

tunnel mode mpls traffic-eng

tunnel mpls traffic-eng priority 0 0

tunnel mpls traffic-eng bandwidth 500

tunnel mpls traffic-eng path-option 1 explicit name test

end

[attrgautam]

I knnow it may sound silly. But did you give

tunnel mpls traffic-eng path-option 2 dynamic

under the TE tunnel

Regds

[olorunloba]

I didn't. I was testing in a lab environment and wanted to know why the dynamic option did not work. I feel that the dynamic path should be able to find a path even if there is only to setup the tunnel.

And it does not sound silly to me.

[attrgautam]

Sorry to barge in again , is the issue resolved ?

[olorunloba]

Well, like I said, it is a lab scenario, I will have to recreate it. But I'm wondering what the problem could have been?

[Harold Ritter]

If you have the same constraints for the dynamic path-option as for the explicit one, there is no reason for the tunnel not to come up as the dynamic path-option is less restrictive.

The command "sh mpls traffic-eng topology path destination " should tell you whether the tunnel would come up or not.

Hope this helps,

[olorunloba]

I found out what the problem was, not enough bandwidth on the physical interface to accomodate the TE.

What I now wonder is the reason the TE came up with a path explicitly stated? Should the bandwidth constraint not apply to it also.

Harold, please kindly explain the output of the command you gave in your post.

[Harold Ritter]

The tunnel with explicit path-option should have had the same issue as with the dynamic path-option.

The command I recommended tells you if a tunnel could be establish and what the path would be.

Hope this helps,