Question:
Ok so we are in
the middle Catalyst 3560V2 Price of designing our new service provider network to offer IPVPN's and
leased line internet, now i have a problem which im hoping you might be able to
help out with. In summary importing multiple default routes into a premium
leased line internet VRF and Buget DSL internet with the DSL internet using the
"budget" internet transit carrier.
So we are
recieving 2 default routes from our IP Transit:
PE1:
show ip bgp
vpnv4 vrf IP_Transit
BGP table
version is 7, local router ID is 169.254.0.0
Status codes: s
suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale, m
multipath, b backup-path, f RT-Filter,
x best-external, a
additional-path, c RIB-compressed,
Origin codes: i
- IGP, e - EGP, ? - incomplete
RPKI validation
codes: V valid, I invalid, N Not found
Network Next Hop Metric LocPrf Weight Path
Route
Distinguisher: 4445:2001 (default for vrf IP_Transit)
* i 0.0.0.0 169.254.0.1 0 100
0 1 i
*> Primary Inet Peer 0 2 i
PE2
show ip bgp
vpnv4 vrf IP_Transit
BGP table
version is 8, local router ID is 169.254.0.1
Status codes: s
suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale, m
multipath, b backup-path, f RT-Filter,
x best-external, a
additional-path, c RIB-compressed,
Origin codes: i
- IGP, e - EGP, ? - incomplete
RPKI validation
codes: V valid, I invalid, N Not found
Network Next Hop Metric LocPrf Weight Path
Route
Distinguisher: 4445:2001 (default for vrf IP_Transit)
* i 0.0.0.0 169.254.0.0 0 100
0 2 i
*> 1.1.1.1 0 1 i
When importing
a default between IP_Transit vrf and DIA (direct internet access) import map removed for the moment. Also one
way importing for the moment.
PE1
ip vrf DIA
rd 4445:2000
route-target
export 4445:2000
route-target
import 4445:2000
route-target
import 4445:2001
ip vrf
IP_Transit
rd 4445:2001
route-target
export 4445:2001
route-target
import 4445:2001
PE2
ip vrf DIA
rd 4445:2000
route-target
export 4445:2000
route-target
import 4445:2000
route-target
import 4445:2001
ip vrf
IP_Transit
rd 4445:2001
route-target
export 4445:2001
route-target
import 4445:2001
I only get the
best path being imported:
PE1
show ip bgp
vpnv4 vrf DIA
Network Next Hop Metric LocPrf Weight Path
Route Distinguisher:
4445:2000 (default for vrf DIA)
*> 0.0.0.0 Primary Inet Peer 0 2 i
PE2
show ip bgp
vpnv4 vrf DIA
Network Next Hop Metric LocPrf Weight Path
Route
Distinguisher: 4445:2000 (default for vrf DIA)
*> 0.0.0.0 1.1.1.1 0 1 i
^--- Is there a
reason why i wouldnt see both routes since PE1&2 are importing there best paths within this
vrf?----^
So what I
actually want for this VRF (DIA) is for PE2 to use PE1 for 0.0.0.0/0
rather than its EBGP neighbor, but we dont have that in the BGP table for me to
apply a route-map to.
I would just
apply a route-map statement to the IP_Transit VRF to set local preference to 0.0.0.0/0
on PE1 however will face the same issue when I create a Budget DSL Internet VRF
which would use the economy provider with backup to PE1
For reference a
Customers bgp table (Global) connecting the PE1 (10.173.100.0) & 2
(10.173.100.2)
show ip bgp
BGP table
version is 34, local router ID is 192.168.1.2
Status codes: s
suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale, m
multipath, b backup-path, x best-external, f RT-Filter
Origin codes: i
- IGP, e - EGP, ? - incomplete
Network
Next Hop Metric LocPrf Weight Path
* 0.0.0.0 10.173.100.2 200 0 4445 1 i
*> 10.173.100.0 100 0 4445 2 i
Answer:
the use of
different route distinguisher on different PE nodes is quite common.
>> do you
know if there is a logical reason why when you import a route between vrfs
(IP_Transit -> DIA) on PE1 the route doesn't appear on PE2 requiring you to
import the routes on PE2 as well?
This is to be
expected the imported route in vrf DIA is not re-advertised in vpnv4
address-family so each device has to perform the necessary import action.
Importing is an
action that has local node scope.
The reason for
this is routing loop avoidance.
PE2 should
import the best path from VRF IP_transit to VRF DIA, if the direct eBGP session
with AS2 fails it should be able to pick up the route learned by PE1 and
propagated in vpnv4 to PE2.
You should test
what happens Catalyst 3560V2 in case of this type of failure to validate your design.
