LDP FRR

[anil12345]

Can I use LDP FRR for acheving faster convergence in my MPLS backbone. Is it an IEEE standard mechanism for acheving faster convergence like MPLS_TE using RSVP.

[drubiogr]

Hi,

There is no LDP based FRR, you have to use TE FRR.

You have the option of IPFRR (IP Fast Reroute) which is *not* RSVP based but IGP based and provides a similar protection to TE FRR Link Protection. This is available today only in IOS-XR for ISIS.

http://www.cisco.com/en/US/partner/docs/ios_xr_sw/iosxr_r3.8/routing/configuration/guide/rc38isis.html#wp1274226

Rgds,

Daniel

[anil12345]

Daniel,

I think LDP FRR is al togather a different mechanism. Not heard from cisco about this feature. I am putting a link from Huawei in regard to LDP FRR.

www.huawei.com/products/datacomm/pdf/view.do?f=60

regards

Anil Dantu

[drubiogr]

Thanks a lot for the link Anil,

Indeed, Cisco is not implementing LDP FRR and I did not hear any plans to support it in the near future, we went for the IPFRR option which by the way can also protect MPLS traffic.

Best regards,

Daniel

[anil12345]

Hi Daniel,

can paste basic configuration for IP FRR. I am not able to access the Link sent by you earlier as it is giving restricted link.

Thanks & regards

Anil

[Harold Ritter]

Anil,

Try this one instead.

http://www.cisco.com/en/US/docs/ios_xr_sw/iosxr_r3.8/routing/configuration/guide/rc38isis.html#wp1274226

Regards

[drubiogr]

Hi Anil,

Here an example of IPFRR configuration. Note that you have to enable it on a per interface basis.

router isis 1

set-overload-bit on-startup 360

is-type level-2-only

net 47.0001.0004.0004.0004.00

nsf ietf

log adjacency changes

address-family ipv4 unicast

metric-style wide

!

interface Loopback0

passive

address-family ipv4 unicast

!

!

interface GigabitEthernet0/7/1/0

circuit-type level-2-only

bfd minimum-interval 50

bfd multiplier 3

bfd fast-detect ipv4

point-to-point

address-family ipv4 unicast

ipfrr lfa level 2

!

Rgds,

Daniel

[anil12345]

Hi,

Some queries in regard to IP FRR.

a) Is IP FRR supported in IS-IS only;is it supported for OSPF.

b) Can I implement IP FRR in my MPLS backbone for fast convegence instead of MPLS TE.

And is the configuration that simple; only one command between neigboring routers.

ipfrr lfa level 2 + BFD commands

3) Which one is recommended IP FRR or MPLS -TE FRR for link failure/ Node failure protection & convergence times around 150ms as I am going to carry voice traffic across my MPLS Backbone.

[drubiogr]

Hi,

To answer your questions:

a) IPFRR is only supported today for ISIS, OSPF is in the roadmap but not available yet

b) Yes, you can implement IPFRR in the core instead of TE FRR to protect IP and MPLS traffic

c) The pro's of IPFRR are its simplicity, requires no interoperability, requires no signaling and no IGP extension. The con's, it does not offer 50msec reroute for all types of failures as TE FRR. Statistically speaking it can offer ~50msec for ~75% of the link failures

Rgds,

Daniel

[Sherif Atef Ahmed Ismail]

Hi Daniel/All

I have few questions please

1- If we used IPFRR to protect MPLS traffic, does this mean there would be a label assigned to backup paths ?

2- If yes then what the difference between this and LDP FRR as according to what I understand whole objective of LDP is to assign a label so if a label is assigned by IPFRR then technically they should be the same , correct ?

3- You mentioned "Statistically speaking it can offer ~50msec for ~75% of the link failures"

I believe this would be the case with pre-prefix protection (i.e. not per-link protection) .. Now the question is there a way to find out what are the prefixes that were not protected by IPFRR ?

Million thanks for your assistance

Regards

Sherif Ismail

[Sherif Atef Ahmed Ismail]

Dears

For the rest, replies are in below url

https://supportforums.cisco.com/thread/2243932

Regards

Sherif Ismail