10-18-2013 08:46 PM - edited 03-07-2019 04:06 PM
Hi All,
Please help me to achive inbound load sharing on my 2 Internet Routers which are connected to 2 different ISP's Routers.
I tried to achive this via as-path prepend but not sure what mistake I am doing that still inbound traffic is going via one link only and no traffic on second link.
NOTE: As per ISP they have made one router as primary due to lower router ID of that router
Below is the config which I have applied on my both the routers but still i am not able to see the load sharing happening on both the links.
NOTE: I have 2 subnets which are advertised to internet
199.63.1.0 /24
199.63.3.0/24
But subnet 199.63.1.0 /24 have more traffic as it is used for my VPN Cpnnectivity than 199.63.3.0 /24 which is used for B2B connectivity.
I tried to device the /24 subnet to 2 times /25 subnet and tried to load share.
Please help me and let me know if you need any more info to fix this issue.
===================
HGC Router
===================
route-map Primary_Prepend permit 10
match ip address 50
route-map Primary_Prepend permit 20
matach ip address 60
set as-path prepend 64779
!
access-list 50 permit 193.63.1.0 0.0.0.127
access-list 50 permit 193.63.3.128 0.0.0.127
!
access-list 60 permit any
!
router bgp 64779
neighbor 203.192.137.109 route-map Primary_Prepend out
!
++++++++++++++++++++++++++++++
PCCW Router
=====================
!
route-map Backup_Prepend permit 10
match ip address 50
route-map Backup_Prepend permit 20
match ip address 60
set as-path prepend 64779
!
access-list 50 permit 193.63.1.128 0.0.0.127
access-list 50 permit 193.63.3.0 0.0.0.127
!
access-list 60 permit any
!
router bgp 64779
neighbor 203.192.145.49 route-map Backup_Prepend out
!
==================================================
10-18-2013 11:14 PM
Hi Vishwas,
Please check this link:
It not via BGP but still can hep to understand:)
https://supportforums.cisco.com/thread/2212769
Regards
10-18-2013 11:46 PM
Hi Vishwas,
You can implement OER/PFR rechnolgy which will help you share inbound and outbound load sharing of ISP link terminated on differemt routers. You will have to run BGP.
Regards,
Sathvik K V
10-19-2013 01:28 AM
Hello,
Both of your network (1.0/24 and 3.0/24) are seems to be originating from AS10026 (Pacnet) on internet which means either you are connected to single ISP or prefix from other ISP is not prefered.
Few query:
1/ Does this IP (199.63.1.024 and 199.63.3.0/24) was assigned by ISP or did you taken from internet registry. If it belongs to one ISP then other ISP will not accept it, so there is no way you can load share it.
2/ If you are attached to single ISP at two different location (or router) you may try below config.
ip prefix-list POOL-HALF-1 SEQ 5 permit 199.63.1.0/25
ip prefix-list POOL-HALF-1 SEQ 10 permit 199.63.3.0/25
ip prefix-list POOL-HALF-2 SEQ 5 permit 199.63.1.128/25
ip prefix-list POOL-HALF-2 SEQ 10 permit 199.63.3.128/25
route-map LINK1 permit 10
match ip address prefix-list POOL-HALF-1
route-map LINK1 permit 30
match ip address prefix-list POOL-HALF-2
set as-path prepend 64779 64779
router bgp 64779
neighbor 203.192.137.109 route-map LINK1 out
route-map LINK2 permit 10
match ip address prefix-list POOL-HALF-2
route-map LINK2 permit 30
match ip address prefix-list POOL-HALF-1
set as-path prepend 64779 64779
router bgp 64779
neighbor 203.192.145.49 route-map LINK2 out
Let me know if more help/understanding required
Regards # Mahesh
10-19-2013 06:27 AM
Thanks Mahesh for the details info and script.
1/ Does this IP (199.63.1.024 and 199.63.3.0/24) was assigned by ISP or did you taken from internet registry. If it belongs to one ISP then other ISP will not accept it, so there is no way you can load share it. -
Answer to your query is: These IPs are not provided by ISP , its my own internet registry IPs.
I have taken 2 Internet links from same ISP PACnet but itslocal PTT are HGC & PCCW.
The config you sent me , do I have to apply it on one CE router or on both of my CE routers ?
I tried the same concept shown in my intial post but still i was not seeing inbound traffic on PCCW Link.
Please let me know if you need anything else from my side to make it working ?
10-19-2013 10:57 PM
Mahesh,
I tried your script and run it on my both the routers and unfortunately my whole traffic was stopped and not working.
I checked with my ISP PACnet and they informed me :
that we only accept /24 and for /25 its no longer routable towards the internet.
Is there any other way to load labalce the inbound traffic ?
10-19-2013 11:02 PM
Then I tried to sub devide 1.0/24 & 3.0/24 network one from each link. then also its not working
One more thing I observed that after creating teh access-list or prefix-list I don't get any matches on 199.63.1.0/24 and 3.0/24
Not sure why i am not getting any matches & thats the reason my traffic is not balanced on both the links.
Any idea why it is happening like this ?
10-21-2013 07:32 PM
Hello,
Since your ISP do not allow
something like below
ip prefix-list POOL1 SEQ 5 permit 199.63.1.0/24
ip prefix-list POOL2 SEQ 5 permit 199.63.3.0/24
route-map LINK1 permit 10
match ip address prefix-list POOL1
!
route-map LINK1 permit 30
match ip address prefix-list POOL2
set as-path prepend 64779 64779
!
route-map LINK1 permit 40
router bgp 64779
neighbor 203.192.137.109 route-map LINK1 out
route-map LINK2 permit 10
match ip address prefix-list POOL2
!
route-map LINK2 permit 30
match ip address prefix-list POOL1
set as-path prepend 64779 64779
!
route-map LINK2 permit 40
router bgp 64779
neighbor 203.192.145.49 route-map LINK2 out
Regards # Mahesh
10-21-2013 10:17 PM
Mahesh,
I have tried this as well. but still not working.
Below is the config taken from router:
============================
HK25-HGCrouter-60M#sh access-lists
Standard IP access list 50
10 permit 193.63.1.0, wildcard bits 0.0.0.255
HK25-HGCrouter-60M#sh run | s route-map
neighbor 203.192.137.109 route-map Primary_Prepend out
route-map Primary_Prepend permit 10
match ip address 50
set as-path prepend 64779 64779 64779
route-map Primary_Prepend permit 20
====================
HK25-PCCWrouter-60M# sh access-lists
Standard IP access list 50
10 permit 193.63.3.0, wildcard bits 0.0.0.255
HK25-PCCWrouter-60M#sh run | s route-map
neighbor 203.192.145.49 route-map Backup_Prepend out
route-map Backup_Prepend permit 10
match ip address 50
set as-path prepend 64779 64779 64779
route-map Backup_Prepend permit 20
10-22-2013 01:00 AM
Hello Vishwas,
When you announced two prefix to two different peering did you checked reverce trace from route-server (You may find it on traceroute.org website).
Based on above trace you may check whether reverce trace is coming back via,. two different path or not.
Alternately you may ask PACNET to provide reverse trace from their GW router.
Regards
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