MPLS and dual equal-cost paths

If a site has two outbound WAN routers (for redundancy) that are configured as PE routers with the WAN interfaces configured with MPLS, will two LSPs be created using LDP (one from each PE) allowing the WAN routers to loadbalance traffic across the MPLS backbone?

Load balancing is very much possible in MPLS environment. Following are the general rules for load balancing labeled packets
1. If the MPLS payload is an IPV4 packet, the load balancing is done by hashing the source and destination IP address of the IPv4 header
2.IF the MPLS payload is an IPv6 packet, the load balancing is done by hashing the source and destination IP address of the IPv6 header.
3.If the MPLS payload is not an IPv4 packet, the load balancing is done by looking at the value of the bottom label
Label stack does not have protocol identifier field so to know what is the MPLS payload is, router can look first nibble following the MPLS label stack, if it is 4 then router considers this an IPv4 packet and performs IPv4 CEF hashing. if it is 6 , MPLS payload is considered IPv6, and the router performs IPv6 CEF hashing
For more information you can refer book "MPLS fundamentals" by Luc De Ghein.

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  • Nexus 7010 OSPF Equal Cost Paths

    Hello,
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    Scott
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  • EIGRP- Equal Cost Paths Selection

    Hello,
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    Best, ~sK       

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  • OSPF equal cost path

    Hi all,
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  • OSPF Equal Cost Path Selection

    This is a nerdy enough qeury in reality.
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    Have a look at the enclosed jpeg to get an idea.
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    It can go through ANY of the other edge switches for a total cost of 40, but it will choose a particular one. What criteria does OSPF use to select this path?
    Remember, the path costs are equal, they are all intra-area.
    I tried messing with Router ID, but this doesn't seem to be it.
    I tried highest interface IP addresses, but it doesn't seem to be this.
    It is not a random act, the algorithm chooses the same one every time.
    There must be some parameter in the LSDB that is the defining one when it comes to path selection.
    Can you help me out please. I need someone who understands the OSPF algorithm better than I do (which might not be hard!).
    Appreciate any comments for debate.

    Disclaimer
    The  Author of this posting offers the information contained within this  posting without consideration and with the reader's understanding that  there's no implied or expressed suitability or fitness for any purpose.  Information provided is for informational purposes only and should not  be construed as rendering professional advice of any kind. Usage of this  posting's information is solely at reader's own risk.
    Liability Disclaimer
    In  no event shall Author be liable for any damages whatsoever (including,  without limitation, damages for loss of use, data or profit) arising out  of the use or inability to use the posting's information even if Author  has been advised of the possibility of such damage.
    Posting
    My guess (as I haven't re-read the RFC), selection of an ECMP to retain in a routing table (assuming all possible ECMP are not retained) and/or exactly how packets or flows are ECMP routed is implementation dependent.
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  • ECMP - equal cost multi path

    Hi,
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    Disclaimer
    The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
    Liability Disclaimer
    In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
    Posting
    The concept behind ECMP is to actively and concurrently take advantage of multiple link/path bandwidth.
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  • OSPF Equal Cost (multiple links) but unbalanced traffic

    Hi!
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    Appreciate if I could receive some help to solve the issue
    Thank you very much  in advance!
    Best Regards,
    asakurahao

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  • RIP/EIGRP maximum number of Equal cost routes

    I am looking for documentation on:
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  • Cost difference between PM report MCI8 and IW38 orders cost

    Hi Experts!
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    Hello,
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    Regards
    Naveen

  • Issue with HP Z820 64GB RAM and dual Quadro K4000's and rendering and playback performance

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  • If equal cost routes exist, OSPF uses CEF load balancing?

    Hi All,
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    Disclaimer
    The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
    Liability Disclaimer
    In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
    Posting
    Rick is correct, but if his response, with mine, causes any confusion. . .
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    I suspect the latter question is what the OP really had in mind, but again, Rick is correct to distinguish that OSPF doesn't use CEF.

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    Disclaimer
    The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
    Liability Disclaimer
    In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
    Posting
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