Cisco Bug: CSCun26512 - dhcp relay support with URPF cause DROP at INGRESS using customer topo
Sep 17, 2018
- Cisco Nexus 6000 Series Switches
Known Affected Releases
Symptom: dhcp relay support with URPF cause DROP at INGRESS using customer topo Conditions: configuring DHCP Relay and URPF on interface vlan 363 on the N6K-14a and N6K-14b switches, if the DHCP Discover (client broadcast) arrived at N6K-14b (Active HSRP), then the DHCP Relay will forward the DHCP discover packet from N6K-14b as uni-cast (using DHCP Relay) to N5K48-2 and then to the DHCP server, then the DHCP server could uni-cast a Offer back through N5K48-1 and over to N6k-14a, then these offers has to be forwarded to the N6K-14b since URPF is configured on the DHCP Discover was send from N6K-14b. The issue is, if this is the route that was traversed for the DHCP Offer, then once the DHCP Offers are send back to N6K-14b over the MCT, the MCT (VPC10) drops the DHCP Offers.
Bug details contain sensitive information and therefore require a Cisco.com account to be viewed.
Bug Details Include
- Full Description (including symptoms, conditions and workarounds)
- Known Fixed Releases
- Related Community Discussions
- Number of Related Support Cases