MPLS Traffic Load Sharing

What is the best way to configure a load sharing policy from multiple CE "remotes" to two CE "hosts" in a MPLS network? Currently, all incoming traffic goes to only one host from the PE.

Hi,
you need to have a look at the complete routing architecture to understand possibilities/responsibilities.
Mainly load distribution for a single prefix can only occur, if more than one path to a destination is known. This however might not be given in the MPLS network. The underlying reason is that BGP will only send the best path in an update - but not all pathes a BGP speaker knows of (RFC mandates this).
As practically all larger BGP implementations use Route Reflectors, which are (RFC conforming) BGP speakers, they will only forward the best path to a destination. The result is:
IF more than one path to a destination network exists and is sent to the RR through different PE routers (with same RD) then only one path will be distributed to all other PE routers.
In this scenario load sharing for a single prefix can not occur, because only one routing table entry exists for this prefix in most if not all PE routers. All you can do is to try to load share by selecting different pathes for different destination prefixes by influencing routing metric. This way part of your traffic will go one way and part will take another path.
IF the SP however uses different RD values for every VRF and the proper "maximum-path" statements in MP-BGP, then load sharing per prefix can be achieved in the MPLS network. The customer however can not influence the SP setup.
Hope this Helps! Please rate all posts.
Regards, Martin

Similar Messages

  • MPLS VPN load sharing when multihoming

    Any one know of best practices for outbound load balancing when multihoming to 2 different service providers in an mpls vpn.
    I have referred to this document (http://www.cisco.com/warp/public/459/40.html) which states the only way to do this is by assigning metrics/weights to a certain range of prefixes learned from one provider, hence load sharing.
    Turning up bgp multipath on the CE would be optimal but since AS PATHs are different the best path selection will be different. Could we possibly turn of best path selection for AS paths (bgp bestpath as-path ignore) and make multipath work? Would that install 2 routes for the same prefix in the RIB?
    Thanks
    Ariful Huq

    Yes you can turn off best path selection for AS path and have multipath work. For a route to be populated in routing table BGP has various metrics for its selection. AS path is one of the metrics it uses for best route selection, so I dont think there should be any problem with it.

  • MP-BGP and MPLS multipath load sharing

    Hi,
    I am trying to PoC MPLS multi path load sharing by using per-PE-per-VRF RDs in the network.
    I have a simple lab setup with AS65000 which consists of SITE1 PE1&PE2 routers (10.250.0.101 and 10.250.0.102), route reflector RR in the middle (10.250.0.55) and SITE2 PE1&PE2 routers (10.250.0.201 and 10.250.0.202). PE routers only do iBGP peering with centralized route reflector and passing route to 10.1.1.0/24 prefix (learned from single CE router) with 100:1 and 100:2 RDs for specific VRF.
    Route reflector gets routes with multiple RDs, makes copies of these routes in order to make local comparison to RD 55:55 configured, uses these routes and install multiple paths into its routing table (all PE routers and RR have "maximum-paths eibgp 4" configured):
    RR#sh ip bgp vpnv4 all
    BGP table version is 7, local router ID is 10.250.0.55
    Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
                  r RIB-failure, S Stale
    Origin codes: i - IGP, e - EGP, ? - incomplete
       Network          Next Hop            Metric LocPrf Weight Path
    Route Distinguisher: 55:55 (default for vrf VRF-A) VRF Router ID 10.250.0.55
    * i10.1.1.0/24      10.250.0.102             0    100      0 65001 i
    *>i                 10.250.0.101             0    100      0 65001 i
    Route Distinguisher: 100:1
    *>i10.1.1.0/24      10.250.0.101             0    100      0 65001 i
    Route Distinguisher: 100:2
    *>i10.1.1.0/24      10.250.0.102             0    100      0 65001 i
    RR#sh ip route vrf VRF-A
    <output omitted>
         10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
    B       10.1.1.0/24 [200/0] via 10.250.0.102, 00:45:52
                              [200/0] via 10.250.0.101, 00:46:22
    BUT, for some reason RR doest reflects routes with multiple RDs down to SITE2 PE1&PE2 - its own clients:
    RR#sh ip bgp vpnv4 all neighbors 10.250.0.201 advertised-routes
    Total number of prefixes 0
    RR#sh ip bgp vpnv4 all neighbors 10.250.0.202 advertised-routes
    Total number of prefixes 0
    Here comes RR BGP configuration:
    router bgp 65000
    no synchronization
    bgp router-id 10.250.0.55
    bgp cluster-id 1.1.1.1
    bgp log-neighbor-changes
    neighbor 10.250.0.101 remote-as 65000
    neighbor 10.250.0.101 update-source Loopback0
    neighbor 10.250.0.101 route-reflector-client
    neighbor 10.250.0.101 soft-reconfiguration inbound
    neighbor 10.250.0.102 remote-as 65000
    neighbor 10.250.0.102 update-source Loopback0
    neighbor 10.250.0.102 route-reflector-client
    neighbor 10.250.0.102 soft-reconfiguration inbound
    neighbor 10.250.0.201 remote-as 65000
    neighbor 10.250.0.201 update-source Loopback0
    neighbor 10.250.0.201 route-reflector-client
    neighbor 10.250.0.201 soft-reconfiguration inbound
    neighbor 10.250.0.202 remote-as 65000
    neighbor 10.250.0.202 update-source Loopback0
    neighbor 10.250.0.202 route-reflector-client
    neighbor 10.250.0.202 soft-reconfiguration inbound
    no auto-summary
    address-family vpnv4
      neighbor 10.250.0.101 activate
      neighbor 10.250.0.101 send-community both
      neighbor 10.250.0.102 activate
      neighbor 10.250.0.102 send-community both
      neighbor 10.250.0.201 activate
      neighbor 10.250.0.201 send-community both
      neighbor 10.250.0.202 activate
      neighbor 10.250.0.202 send-community both
    exit-address-family
    address-family ipv4 vrf VRF-A
      maximum-paths eibgp 4
      no synchronization
      bgp router-id 10.250.0.55
      network 10.255.1.1 mask 255.255.255.255
    exit-address-family
    SITE1 PE1 configuration:
    router bgp 65000
    no synchronization
    bgp router-id 10.250.0.101
    bgp log-neighbor-changes
    neighbor 10.250.0.55 remote-as 65000
    neighbor 10.250.0.55 update-source Loopback0
    neighbor 10.250.0.55 soft-reconfiguration inbound
    no auto-summary
    address-family vpnv4
      neighbor 10.250.0.55 activate
      neighbor 10.250.0.55 send-community both
    exit-address-family
    address-family ipv4 vrf VRF-A
      neighbor 10.1.101.2 remote-as 65001
      neighbor 10.1.101.2 activate
      neighbor 10.1.101.2 soft-reconfiguration inbound
      maximum-paths eibgp 4
      no synchronization
      bgp router-id 10.250.0.101
    exit-address-family
    SITE1 PE2 configuration is similar to SITE1 PE1. They both do eBGP peering with dualhomed CE router in AS65001 which announces 10.1.1.0/24 prefix into VRF-A table.
    My question is: clearly, the issue is that RR doesn't reflect any routes to its clients (SITE2 PE1&PE2) for 10.1.1.0/24 prefix with 100:1 and 100:2 RDs that dont match it's locally configured RD 55:55 for VRF-A, although they are present in its BGP/RIB tables and used for multipathing. Is this an expected behavior or some feature limitation for specific platform or IOS version? Currently, in this test lab setup I run IOS 12.4(24)T8 on all the devices.
    Please, let me know if any further details are needed to get an idea of why this well known and widely used feature is not working correctly in my case. Thanks a lot!
    Regards,
    Sergey

    Hi Ashish,
    I tried to remove VRF and address family configurations completely from RR.
    router bgp 65000
    no synchronization
    bgp router-id 10.250.0.55
    bgp cluster-id 1.1.1.1
    bgp log-neighbor-changes
    neighbor 10.250.0.101 remote-as 65000
    neighbor 10.250.0.101 update-source Loopback0
    neighbor 10.250.0.101 route-reflector-client
    neighbor 10.250.0.101 soft-reconfiguration inbound
    neighbor 10.250.0.102 remote-as 65000
    neighbor 10.250.0.102 update-source Loopback0
    neighbor 10.250.0.102 route-reflector-client
    neighbor 10.250.0.102 soft-reconfiguration inbound
    neighbor 10.250.0.201 remote-as 65000
    neighbor 10.250.0.201 update-source Loopback0
    neighbor 10.250.0.201 route-reflector-client
    neighbor 10.250.0.201 soft-reconfiguration inbound
    neighbor 10.250.0.202 remote-as 65000
    neighbor 10.250.0.202 update-source Loopback0
    neighbor 10.250.0.202 route-reflector-client
    neighbor 10.250.0.202 soft-reconfiguration inbound
    no auto-summary
    address-family vpnv4
      neighbor 10.250.0.101 activate
      neighbor 10.250.0.101 send-community both
      neighbor 10.250.0.102 activate
      neighbor 10.250.0.102 send-community both
      neighbor 10.250.0.201 activate
      neighbor 10.250.0.201 send-community both
      neighbor 10.250.0.202 activate
      neighbor 10.250.0.202 send-community both
    exit-address-family
    After this, RR doesn't accept any routes at all from S1PE1&S1PE2 routers, thus not reflecting any routes down to its clients S2PE1&S2PE2 as well:
    S1PE1#sh ip bgp vpnv4 all
    BGP table version is 6, local router ID is 10.250.0.101
    Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
                  r RIB-failure, S Stale
    Origin codes: i - IGP, e - EGP, ? - incomplete
       Network          Next Hop            Metric LocPrf Weight Path
    Route Distinguisher: 100:1 (default for vrf VRF-A) VRF Router ID 10.250.0.101
    *> 10.1.1.0/24      10.1.101.2               0             0 65001 i
    S1PE1#sh ip bgp vpnv4 all neighbors 10.250.0.55 advertised-routes
    BGP table version is 6, local router ID is 10.250.0.101
    Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
                  r RIB-failure, S Stale
    Origin codes: i - IGP, e - EGP, ? - incomplete
       Network          Next Hop            Metric LocPrf Weight Path
    Route Distinguisher: 100:1 (default for vrf VRF-A) VRF Router ID 10.250.0.101
    *> 10.1.1.0/24      10.1.101.2               0             0 65001 i
    Total number of prefixes 1
    S1PE2#sh ip bgp vpnv4 all
    BGP table version is 6, local router ID is 10.250.0.102
    Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
                  r RIB-failure, S Stale
    Origin codes: i - IGP, e - EGP, ? - incomplete
       Network          Next Hop            Metric LocPrf Weight Path
    Route Distinguisher: 100:2 (default for vrf VRF-A) VRF Router ID 10.250.0.102
    *> 10.1.1.0/24      10.1.201.2               0             0 65001 i
    S1PE2#sh ip bgp vpnv4 all neighbors 10.250.0.55 advertised-routes
    BGP table version is 6, local router ID is 10.250.0.102
    Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
                  r RIB-failure, S Stale
    Origin codes: i - IGP, e - EGP, ? - incomplete
       Network          Next Hop            Metric LocPrf Weight Path
    Route Distinguisher: 100:2 (default for vrf VRF-A) VRF Router ID 10.250.0.102
    *> 10.1.1.0/24      10.1.201.2               0             0 65001 i
    Total number of prefixes 1
    RR#sh ip bgp vpnv4 all
    RR#sh ip bgp vpnv4 all neighbors 10.250.0.101 routes
    Total number of prefixes 0
    RR#sh ip bgp vpnv4 all neighbors 10.250.0.102 routes
    Total number of prefixes 0
    Any feedback is appreciated. Thanks.
    Regards,
    Sergey

  • MPLS-TE and Load sharing?

    Hi,
    I have been reading and searching for a long time,
    I have an issue with MPLS-TE, ok, let me explain..
    We have
    PE(7600) -> MPLS-network <- PE(7300)
    We have EoMPLS connection between these points
    over 2x STM-1, and we want to lets say,
    STM1(tunnel0) take 155Mbit of link1, and
    STM1(tunnel1) take 155Mbit of link2, so
    we could get full use of both links,
    I use exact path option, and everythings
    works, but, the traffic seems to choose only
    the one of the tunnels..
    Then the question is, with the tag-switching,
    does the traffic tunnels go with the CEF switching
    so, src->dst flows occurs?
    Because if i did like,
    show ip cef dstip internal
    I saw the load sharing all fine..

    Solved,
    Sorry, I found another conversation that pointed
    my conclusion out,
    http://forum.cisco.com/eforum/servlet/NetProf?page=netprof&CommCmd=MB%3Fcmd%3Ddisplay_location%26location%3D.1dd62298
    Best Regards,
    Kjarri.

  • Load sharing traffic VIP cisco ACE

    Hi,
    I am asking me if it is possible to load sharing traffic itend to a vip with two serverfarm.
    I would like to have two serverfarm active no active/backup for my vip.
    Thanks for help.
    Regards.

    Merge the 2 serverfarms into a single one.
    Gilles.

  • MPLS TE load-balancing --- CEF Problem

    Dears
    Would like your assistance please regarding below issue
    We are having 5 TE tunnels going to same destination and we are doing load-balancing between these 5 LSPs TE tunnels.
    Command "mls ip cef load-sharing full simple" is configured so that CEF will use L4 ports in its algorithm
    Problem that due to CEF behavior, 2 link are v.highly utilized and the other 3 utilization are below average
    What I am thinking of but not sure If this will help or not is to have 2 TE tunnels instead of 5
    1 TE tunnel load balancing on 3 links ( This can be done by using static route to tail loopback poiting to the 3 links) and another TE tunnel load balancing on the other 2 links
    By doing this, I think CEF would be used 2 times; first to determine which TE tunnel to use then to determine which link within the tunnel
    Will this help ?
    For example
    interface Tunnel1
    ip unnumbered Loopback0
    mpls ip
    tunnel destination 10.0.0.1
    tunnel mode mpls traffic-eng
    tunnel mpls traffic-eng autoroute announce
    tunnel mpls traffic-eng path-option 1 dynamic
    tunnel mpls traffic-eng fast-reroute
    ip route 10.0.0.1 255.255.255.255 link-1
    ip route 10.0.0.1 255.255.255.255 link-2
    ip route 10.0.0.1 255.255.255.255 link-3

    Hello Sherif,
    traffic of a single TE tunnel will not be load balanced over multiple physical links as the TE tunnel is setup using a reservation and the path will use only one link for each router hop.
    So moving to two TE tunnels is not an option for you.
    Hope to help
    Giuseppe

  • Load sharing/balancing between 2 Service Providers

    Hi,
    I have a scenario where I have the following and this is repeated at different sites globally.
    CE1-----------PE1_SP1---MPLS cloud
    |
    CE1---standby--PE2_SP1---MPLS cloud
    CE2-----------PE1_SP2----MPLS Cloud
    |
    CE2---standby--PE2_SP2---MPLS Cloud
    2 different service providers and we require load sharing/balancing to both SP1 and SP2.
    If either of the SP's PE router is down it should bring up the standby link.
    2 ASN, not sure if I can load share different prefixes in this scenario.
    Will the applications fail?
    Will the traffic flow be symmetric ?
    Any help is very much appreciated.
    Thanks,
    Paul

    Hello Paul,
    if you are using a single CE router on each site.
    to get load-balancing on your CEx:
    router bgp X
    maximum-paths 2
    eBGP load-balancing is easier so 2 ISP ASN is fine
    Verify that you have flow based load-balancing and everything should be fine.
    Notice that you have a failure on site N of provider1 you can be able to detect it in all remote sites only if they are receiving the routes of all the sites. If receiving a default route there's no way for other sites to detect the failure.
    If receiving all the prefixes after MP-BGP convergence in ISP1 site N's prefixes will be withdrawn and will be reachable only via ISP2.
    To use an active/standby
    on all Cex
    router bgp x
    neighbor PE-ISP1 weigth 500
    neighbor PE-ISP1 fast-external-fallover
    in this way until a prefix is present in ISP1 MP-BGP traffic is sent via ISP1
    If using two CE in each site things are a little more complex and you need an iBGP session between them.
    Hope to help
    Giuseppe

  • Discussion on load-balance and load-sharing

    Hi, I found a article, which discuss the difference between load-balance and load-sharing. I think the explanation is pretty good, please see below. But I still have a question: how can we decide to choose one the both balance in the production environment ?  Thank you
    "In short, load balancing tries to distribute traffic evenly over multiple paths, whereas, load sharing intends to do it (for the lack of a better term) equally.  True load balancing is difficult to achieve.  For example, let's say there were two links (100 mbps and 300 mpbs) and a router needed to send out 600 mbps of traffic.  Load balancing would distribute the traffic evenly, sending 300 mbps on each link.  On the contrary, load sharing would divide the traffic equally based on the available resources, sending 200 mbps on the slower link and 400 mbps on the faster one. "

    Disclaimer
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    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
    That's not how Cisco uses the terms, and generically they are often used almost interchangeably.
    Cisco uses load balancing as the catch all for how a single L3 device routes across multiple paths to the same destination.  Equal metrics or equal actual load distribution are not required.  Most often, load balancing will be discussed with ECMP, but unequal path loading balancing will include Cisco's proprietary IGPs, such as EIGRP.
    Cisco uses load sharing when using multiple paths when a single L3 devices doesn't normally route across multiple paths or multiple L3 devices are involved.  Cisco load sharing discussions usually revolve around BGP.
    Generically, I would say load balancing has more of a dynamic aspect to it, i.e. something is trying to actively balance traffic across multiple paths, while load sharing might mean multiple paths are utilized but not actively dynamically balanced.
    I'm unsure what's your question with a production environment.

  • Load-balancing vs Load-sharing (L2/L3)

    What is the difference in load balancing and load sharing. Can you generalize load-balancing to layer two? Or layer three protocols also do this, except BGP?
    FHRPs like VRRP, GLBP, and HSRP are essentially load sharing protocols (except GLBP though). Loop prevention mechanisms like MSTP, G.8032, and REP also do not do load balancing I guess. Instead they offer a way to distribute (share) traffic over multiple links unevenly. Why do people still call it load-balancing?
    While link aggregation may truly be considered load balancing. Where traffic can be balanced based on a few attributes ( src-dst/mac, ip, port).
    And what role does fast-switching/process-switching play in load balancing. I am aware that these are the very processes that ultimately do load-balancing, given enough equal cost paths. Does CEF really take load balancing to another level? It still does the same job, but by caching flow data (RIB) to the CEF table, doesn't it?
    Incase of IGP, load-balancing may be possible, but BGP just doesn't support it. Because it only selects one best route (?). Even with multipath, BGP advertises best path only; it does install multiple routes in routing table though. So IGP does the balancing?

    What is the difference in load balancing and load sharing. Can you generalize load-balancing to layer two? Or layer three protocols also do this, except BGP?
    FHRPs like VRRP, GLBP, and HSRP are essentially load sharing protocols (except GLBP though). Loop prevention mechanisms like MSTP, G.8032, and REP also do not do load balancing I guess. Instead they offer a way to distribute (share) traffic over multiple links unevenly. Why do people still call it load-balancing?
    While link aggregation may truly be considered load balancing. Where traffic can be balanced based on a few attributes ( src-dst/mac, ip, port).
    And what role does fast-switching/process-switching play in load balancing. I am aware that these are the very processes that ultimately do load-balancing, given enough equal cost paths. Does CEF really take load balancing to another level? It still does the same job, but by caching flow data (RIB) to the CEF table, doesn't it?
    Incase of IGP, load-balancing may be possible, but BGP just doesn't support it. Because it only selects one best route (?). Even with multipath, BGP advertises best path only; it does install multiple routes in routing table though. So IGP does the balancing?

  • CEF Load Sharing Recursive Lookup

    Hi,
    i have this scenario:
    | ----P1----P2---|
    PE1----| |----PE2
    | ----P3----P4---|
    IP Loop PE1: 5.5.5.5
    There are 2 Gigabitethernet betweenn the router PE and the router P.
    PE1 advertise 1.1.1.1/32 to PE2:
    PE2#sh ip route 1.1.1.1
    Routing entry for 1.1.1.1/32
    Known via "bgp 65000", distance 200, metric 0, type internal
    Last update from 5.5.5.5 01:57:03 ago
    Routing Descriptor Blocks:
    * 5.5.5.5, from 4.4.4.4 , 01:57:03 ago
    Route metric is 0, traffic share count is 1
    AS Hops 0, BGP network version 0
    PE2 has 4 link (2 towards P2 and 2 towards P4) at equal cost to reach 5.5.5.5/32 via OSPF:
    PE2# sh ip route 5.5.5.5
    Routing entry for 5.5.5.5/32
    Known via "ospf 65000", distance 110, metric 200, type inter area
    Last update from 23.23.23.24 on GigabitEthernet8/0/0, 01:13:45 ago
    Routing Descriptor Blocks:
    * 22.22.22.21, from IP-P1, 01:13:45 ago, via GigabitEthernet3/0/0
    Route metric is 200, traffic share count is 1
    23.23.23.23, from IP-P1, 01:13:45 ago, via GigabitEthernet8/0/0
    Route metric is 200, traffic share count is 1
    22.22.22.22, from IP-P2, 01:13:45 ago, via GigabitEthernet3/0/0
    Route metric is 200, traffic share count is 1
    23.23.23.24, from IP-P2, 01:13:45 ago, via GigabitEthernet8/0/0
    Route metric is 200, traffic share count is 1
    If I look cef table I have all the 4 link too:
    PE2# sh ip cef 5.5.5.5
    5.5.5.5/32, version 3101050, epoch 0, per-destination sharing
    0 packets, 0 bytes
    Flow: AS 0, mask 32
    tag information set, shared, all rewrites owned
    local tag: 1541
    via 22.22.22.21, GigabitEthernet3/0/0, 14 dependencies
    traffic share 1
    next hop 22.22.22.21, GigabitEthernet3/0/0
    valid adjacency
    tag rewrite with Gi3/0/0, 22.22.22.21, tags imposed {390}
    via 23.23.23.23, GigabitEthernet8/0/0, 14 dependencies
    traffic share 1
    next hop 23.23.23.23, GigabitEthernet8/0/0
    valid adjacency
    tag rewrite with Gi8/0/0, 23.23.23.23, tags imposed {390}
    via 22.22.22.22, GigabitEthernet3/0/0, 15 dependencies
    traffic share 1
    next hop 22.22.22.22, GigabitEthernet3/0/0
    valid adjacency
    tag rewrite with Gi3/0/0, 22.22.22.22, tags imposed {390}
    via 23.23.23.24, GigabitEthernet8/0/0, 15 dependencies
    traffic share 1
    next hop 23.23.23.24, GigabitEthernet8/0/0
    valid adjacency
    tag rewrite with Gi8/0/0, 23.23.23.24, tags imposed {390}
    0 packets, 0 bytes switched through the prefix
    tmstats: external 0 packets, 0 bytes
    internal 0 packets, 0 bytes
    But if i Look the cef table for the address 1.1.1.1/32 I have only 1 link:
    PE2# sh ip cef 1.1.1.1
    1.1.1.1/32, version 6477717, epoch 0, per-destination sharing
    0 packets, 0 bytes
    Flow: AS 0, mask 32
    tag information from 5.5.5.5/32, shared, all rewrites owned
    local tag: 1541
    via 5.5.5.5, 0 dependencies, recursive
    next hop 22.22.22.22, GigabitEthernet3/0/0 via 5.5.5.5/32 (Default)
    valid adjacency
    tag rewrite with Gi3/0/0, 22.22.22.21, tags imposed {390}
    Recursive load sharing using 5.5.5.5/32.
    The question is: why PE2 doesn't utilize all the 4 link (towards P2 and P4) to reach 1.1.1.1/32?
    Thanks in advance
    Rgds
    Gianluca

    Although the "show ip cef 1.1.1.1" command only displays one interface, the recursive loadsharing will take place as expected.
    Do a "show ip cef 1.1.1.1 internal", which will show you the 4 outbound interfaces being used.
    Hope this helps,

  • BGP load sharing with bandwidth

    We are running eBGP between two routers. We had a 250 M PVC between the two routers on OSM STM4 ATM interface. We need to increase the B/W between the two routers to 350M, but because there's a limitation on the PVC size for the OSM STM4 ATM card (Max. size of the PVC is 300M), so we created new PVC between the two routers on the same circuits (and of course the same interfaces). Now I need to enable the load sharing between the two routers taking the PVC B/W in consideration.. So I prepared this config, is it right and full? Or Am I missing anything here..
    RouterA:
    Router bgp 100
    Neighbor 10.1.1.1 remote-as 200 (10.1.1.1 is loop back address fro Router B)
    Neighbor 10.1.1.1 ebgp-multihop
    bgp dmzlink-bw
    neighbor 10.1.1.1 dmzlink-bw
    neighbor 10.1.1.1 send-community both
    maximum-paths ebgp 2
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