I have a very weird issue with multicast on nexus 7000, i am running NXOS version 6.2(16)
The setup is the following:
Two Nexus 7710 running in vPC, all SVI are local on these Nexus
There are two access switches, SWITCH01 and SWTICH02
Multicast Source is 10.0.0.254/24 on VLAN 401, which exist only on SWITCH01
Multicast Client is 10.0.2.33/24 on VLAN 403, which exist only on SWITCH02
There is a vPC Po1 to reach SWITCH01 and another Po2 to reach SWITCH02
iperfv3 was used to test network connectivity between server and client
Both SVI are on the Nexus only. both access Switches are simply L2 access with default ip igmp snooping.
I get the following outpost from both Nexus:
N7K-01-DISTRIBUCION-01# show ip mroute 239.0.0.250
IP Multicast Routing Table for VRF "default"
(*, 239.0.0.250/32), uptime: 00:07:19, igmp ip pim
Incoming interface: loopback1, RPF nbr: 10.4.250.9
Outgoing interface list: (count: 1)
Vlan403, uptime: 00:07:19, igmp
(10.0.0.250/32, 239.0.0.250/32), uptime: 00:10:31, ip pim mrib
Incoming interface: Vlan401, RPF nbr: 10.0.0.250
Outgoing interface list: (count: 1)
Vlan403, uptime: 00:07:19, mrib
N7K-02-DISTRIBUCION-02# show ip mroute 239.0.0.250
IP Multicast Routing Table for VRF "default"
(*, 239.0.0.250/32), uptime: 00:07:44, igmp ip pim
Incoming interface: loopback1, RPF nbr: 10.4.250.9
Outgoing interface list: (count: 1)
Vlan403, uptime: 00:07:44, igmp
(10.0.0.250/32, 239.0.0.250/32), uptime: 00:10:56, ip pim mrib
Incoming interface: Vlan401, RPF nbr: 10.0.0.250, internal
Outgoing interface list: (count: 1)
Vlan403, uptime: 00:07:44, mrib
I get the same output from show ip igmp route 239.0.0.250:
N7K-01-DISTRIBUCION-01# show ip igmp route 239.0.0.250
IGMP Connected Group Membership for VRF "default" - matching Group "239.0.0.250"
Type: S - Static, D - Dynamic, L - Local, T - SSM Translated
Group Address Type Interface Uptime Expires Last Reporter
239.0.0.250 D Vlan403 00:08:27 00:03:40 10.0.2.33
N7K-02-DISTRIBUCION-02# show ip igmp route 239.0.0.250
IGMP Connected Group Membership for VRF "default" - matching Group "239.0.0.250"
Type: S - Static, D - Dynamic, L - Local, T - SSM Translated
Group Address Type Interface Uptime Expires Last Reporter
239.0.0.250 D Vlan403 00:08:33 00:03:34 10.0.2.33
And also exact same output for show ip pim route 239.0.0.250:
N7K-01-DISTRIBUCION-01# show ip pim route 239.0.0.250
PIM Routing Table for VRF "default" - 5 entries
(*, 239.0.0.250/32), RP 10.4.250.9*, expires 00:00:56, RP-bit
Incoming interface: loopback1, RPF nbr 10.4.250.9
Oif-list: (0) 00000000, timeout-list: (0) 00000000
Timeout-interval: 1, JP-holdtime round-up: 3
(10.0.0.250/32, 239.0.0.250/32), expires 00:01:58
Incoming interface: Vlan401, RPF nbr 10.0.0.250
Oif-list: (0) 00000000, timeout-list: (0) 00000000
Immediate-list: (0) 00000000, timeout-list: (0) 00000000
Sgr-prune-list: (0) 00000000 Assert-win-oif-list: (0) 00000000
Timeout-interval: 1, JP-holdtime round-up: 3
N7K-02-DISTRIBUCION-02# show ip pim route 239.0.0.250
PIM Routing Table for VRF "default" - 5 entries
(*, 239.0.0.250/32), RP 10.4.250.9*, expires 00:00:29, RP-bit
Incoming interface: loopback1, RPF nbr 10.4.250.9
Oif-list: (0) 00000000, timeout-list: (0) 00000000
Timeout-interval: 3, JP-holdtime round-up: 3
(10.0.0.250/32, 239.0.0.250/32), expires 00:02:36, register
Incoming interface: Vlan401, RPF nbr 10.0.0.250
Oif-list: (0) 00000000, timeout-list: (0) 00000000
Immediate-list: (0) 00000000, timeout-list: (0) 00000000
Sgr-prune-list: (0) 00000000 Assert-win-oif-list: (0) 00000000
Timeout-interval: 3, JP-holdtime round-up: 3
For RP selection, I am using anycast RP:
N7K-01-DISTRIBUCION-01# show ip pim rp
PIM RP Status Information for VRF "default"
BSR disabled
Auto-RP disabled
BSR RP Candidate policy: None
BSR RP policy: None
Auto-RP Announce policy: None
Auto-RP Discovery policy: None
Anycast-RP 10.4.250.9 members:
10.4.250.7* 10.4.250.8
RP: 10.4.250.9*, (0), uptime: 22:48:40, expires: never,
priority: 0, RP-source: (local), group ranges:
224.0.0.0/4
N7K-02-DISTRIBUCION-02# show ip pim rp
PIM RP Status Information for VRF "default"
BSR disabled
Auto-RP disabled
BSR RP Candidate policy: None
BSR RP policy: None
Auto-RP Announce policy: None
Auto-RP Discovery policy: None
Anycast-RP 10.4.250.9 members:
10.4.250.7 10.4.250.8*
RP: 10.4.250.9*, (0), uptime: 23:05:12, expires: never,
priority: 0, RP-source: (local), group ranges:
224.0.0.0/4
N7K-02-DISTRIBUCION-02#
All loopback interfaces are being distribute as passive interfaces by the IGP, there are two dedicated and independent L3 link between the vPC members besides the Peer Link Port Channel. PIM is on and running on all L3 links and all SVI
Finally, by checking "show forwarding multicast outgoing-interface-list" on both Nexus, I see the valid VLANs 401 and 403, but the Nexus never forward a single multicast packet between VLAN 401 and VLAN 403
I already checked the document "Troubleshooting NXOS Multicast" fro Cisco Live and everything seems to be working fine, other than traffic not being forwarded.
