09-20-2013 03:59 AM - edited 03-04-2019 09:06 PM
i have a small lab setup with two PE-routers, two P-routers and a route-reflector. see exhibit
on both pe-roouters directly connected networks in vrf RED, which is redistributed to mBGP/vrf RED
PE1 and PE5 are route-reflector clients to RR
from IGP/OSPF prespective, i have two parallel paths from PE1(loopback 192.168.4.1) to PE5 (loopback 192.168.4.5) and vice versa.
(PE1 <-> P1 <-> PE5 and PE1 <-> P2 <-> PE5)
Both networks from VPN RED use RT 65000:12
RD is 192.168.4.1:12 on PE1 and 192.168.4.4:12 on PE5
with sh ip route vrf RED i see only 1 path to the LAN's (192.168.12.0/22 and 192.168.51.0/24)
this is because PE's are using only one RD for the connected RED networks.
Is there a way to make use of parallel paths in this scenario ?
Solved! Go to Solution.
09-20-2013 04:38 AM
Hi,
You only have one BGP path but this path has a recursive next hop (PE loopback address) and packets to this recursive next hop will be load balanced over the multiple IGP paths. You should be able to see that by doing a "show ip cef vrf RED
Regards
09-20-2013 04:38 AM
Hi,
You only have one BGP path but this path has a recursive next hop (PE loopback address) and packets to this recursive next hop will be load balanced over the multiple IGP paths. You should be able to see that by doing a "show ip cef vrf RED
Regards
09-20-2013 12:20 PM
Hi
you are absolutely right !
r1# show ip cef vrf RED exact-route 192.168.12.3 192.168.51.1
192.168.12.3 -> 192.168.51.1 => label 35 label 24 TAG adj out of Serial0/0/0
r1# show ip cef vrf RED exact-route 192.168.12.1 192.168.51.2
192.168.12.1 -> 192.168.51.2 => label 35 label 25 TAG adj out of FastEthernet0/1, addr 10.10.10.5
btw: do you know why no next-hop ip-addr is shown on Serial while on FastEthernet it shows 10.10.10.5 ?
Both links are configured as /30 and ospf point-to-point.
thanks and regards
09-20-2013 06:23 PM
Hi,
>btw: do you know why no next-hop ip-addr is shown on Serial while on FastEthernet it shows 10.10.10.5 ?
>Both links are configured as /30 and ospf point-to-point.
The reason is that there may be several adjacencies on a broadcast interface (FE0/1), therefore you need the IP address of the next hop to make sure you use the proper one. This is not required on a point to point interface (SE0/0/0).
Regards
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