Funnily enough when I block the loopbacks of Sham going into OSPF it kills my sham link altogether!
The only way I seem to fix this is by doing a no area x sham-link etc etc and then putting the sham-link command back in and poof it all workings. This has been the case several times! Haven't really bothered to investigate why but this solution works for me on physical and GNS3 HTH Sent from my iPhone 4 On 23 May 2011, at 10:03, Nicolas Bellenbaum <[email protected]> wrote: > I've had issues when i block both loopbacks from being redistributed into > OSPF. When i only filtered the loopback local to the PE from being > redistributed into OSPF the sham link came up with no issue. > > Nick > > On May 23, 2011, at 11:31 AM, Jason Maynard wrote: > >> I thought I would run this by the group as I am not getting the expected >> results in GNS3. Is there anything that I am missing when creating >> shamlinks? >> >> >> >> >> >> 1. Create a loopback with a /32 address on PE Routers >> >> 2. Add these loopbacks to the VRF >> >> 3. Advertise these loopbacks into the vrf address-family in BGP (Do >> advertise these networks in OSPF) >> >> 4. Create a shamlink in the OSPF vrf process >> >> 5. Ensure /32 loopback addresses create above are not advertised in OSPF >> >> >> >> Complete Configuration (I only included the relevant information and it is >> assumed the you have an already functioning MPLS network) >> >> >> >> PE1 >> >> >> >> Step 1 and 2 >> >> interface Loopback100 >> >> description SHAMLINK Interface >> >> ip vrf forwarding CUSTA >> >> ip address 11.11.11.11 255.255.255.255 >> >> >> >> Step 3 >> >> router bgp 100 >> >> address-family ipv4 vrf CUSTA >> >> redistribute ospf 14 vrf CUSTA >> >> network 11.11.11.11 mask 255.255.255.255 >> >> exit-address-family >> >> >> >> Step 4 >> >> router ospf 14 vrf CUSTA >> >> area 0 sham-link 11.11.11.11 33.33.33.33 >> >> redistribute bgp 100 subnets route-map SHAM >> >> >> >> Step 5 >> >> access-list 10 permit 33.33.33.33 >> >> access-list 10 permit 11.11.11.11 >> >> ! >> >> route-map SHAM deny 10 >> >> match ip address 10 >> >> ! >> >> route-map SHAM permit 20 >> >> >> >> >> >> >> >> PE2 >> >> >> >> Step 1 and 2 >> >> interface Loopback100 >> >> description SHAMLINK Interface >> >> ip vrf forwarding CUSTA >> >> ip address 33.33.33.33 255.255.255.255 >> >> >> >> >> >> Step 3 >> >> router bgp 100 >> >> redistribute ospf 14 vrf CUSTA >> >> network 33.33.33.33 mask 255.255.255.255 >> >> exit-address-family >> >> >> >> >> >> Step 4 >> >> router ospf 14 vrf CUSTA >> >> area 0 sham-link 33.33.33.33 11.11.11.11 >> >> redistribute bgp 100 subnets route-map SHAM >> >> >> >> Step 5 >> >> access-list 10 permit 33.33.33.33 >> >> access-list 10 permit 11.11.11.11 >> >> ! >> >> route-map SHAM deny 10 >> >> match ip address 10 >> >> ! >> >> route-map SHAM permit 20 >> >> >> >> >> >> >> >> Blog: <http://packetsanalyzed.blogspot.com/> >> http://packetsanalyzed.blogspot.com/ >> >> >> >> _______________________________________________ >> For more information regarding industry leading CCIE Lab training, please >> visit www.ipexpert.com >> >> Are you a CCNP or CCIE and looking for a job? Check out >> www.PlatinumPlacement.com > > _______________________________________________ > For more information regarding industry leading CCIE Lab training, please > visit www.ipexpert.com > > Are you a CCNP or CCIE and looking for a job? Check out > www.PlatinumPlacement.com _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out www.PlatinumPlacement.com
