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IGMP Snooping filtering OSPF except on VLAN 1
Hello, I am experiencing an issue where OSPF routers connectted m4300-series switches running IGMP Snooping are unable to form an adjacency. The m4300-series switches seem to be filtering OSPF mu...
In 12.0.11.x we introduced a new command 'set igmp-plus" which is needed for all reseved multicast addresses to work.
I beliveve following configuration should fix your issue
vlan database
vlan 20
set igmp-plus 20
Hi rgubele ,
Welcome to community,
I just tried a simple networking test to see how OSPF works except for vlan 1, It seems that OSPF neighbors can be set up normally on M4300 12.0.11.10.
I think I need more detailed information about your networking and configuration.
Could you please provide me with your topology and tech support file?
I'm going to try to replicate this issue.
Thank you.
(M4300-96X) #show ip ospf neighbor
Router ID Priority IP Address Neighbor State Dead
Interface Time
--------------- -------- --------------- ----------- ------------------ ----
192.168.20.2 1 192.168.20.2 vlan 20 Full/BACKUP-DR 34
My configuration as follow:
Topo
M4300---M4300
Interface vlan and OSPF configuration:
router ospf
router-id 192.168.20.2
interface vlan 20
routing
ip address 192.168.20.1 255.255.255.0
ip ospf area 0
exit
!
router ospf
router-id 192.168.20.1
interface vlan 20
routing
ip address 192.168.20.2 255.255.255.0
ip ospf area 0
exit
IGMP configuration:
vlan database
vlan 20
set igmp-plus 20
(M4300-96X) #show igmpsnooping
Admin Mode..................................... Enable
Multicast Control Frame Count.................. 2216
IGMP header validation......................... Enabled
Interfaces Enabled for IGMP Snooping........... None
VLANs enabled for IGMP snooping................ 1
20
Report Flood Mode.............................. Enabled
Exclude Mrouter Interface Mode................. Enabled
Operational Mode............................... Enable
Fast Leave Auto-Assignment Mode................ Enable
IGMP-Plus...................................... Enabled
VLAN ID........................................ 20
IGMP Snooping Admin Mode....................... Enabled
Fast Leave Mode................................ Enabled
Group Membership Interval (secs)............... 600
Max Response Time (secs)....................... 120
Multicast Router Expiry Time (secs)............ 300
Report Suppression Mode........................ Disabled
Report Flood Mode.............................. Enabled
Exclude Mrouter Interface Mode................. Enabled
IGMP-Plus...................................... Enabled
(M4300-96X) #show mac-address-table multicast
Fwd
VLAN ID MAC Address Source Type Description Interface Interface
------- ----------------- ------- ------- --------------- --------- ---------
20 01:00:5E:00:00:05 Rsvd-MC Static Network Assist Fwd: Fwd: ---- the ospf multicast address was in vlan 20
ALL ALL
20 01:00:5E:00:00:06 Rsvd-MC Static Network Assist Fwd: Fwd:
ALL ALL
Hi kevin_hong ,
Thank you for your reponse. My architecture is very complex at the moment, but a simplified version would be something like:
[ROUTER] <-> [52G/24X stack] <-> [12x12f] <-> [ROUTER]
Router could be:
- A Cisco device
- A Mikrotik device
- A Linux machine running Quagga (old and new versions)
- A Juniper device
- An Extreme/Brodcade device
Whether a particular port is trunk or access, whether the vlan is tagged or not, doesn't seem to matter.
Some notable differences I see in our configuration:
We're not using IGMP-Plus mode. When I looked at it, it didn't appear to be appropriate for our configuration because we use any-source multicast and IGMPv2. IGMP Plus mode enables report flooding, which in theory should activate host report suppression and wouldn't work. Additionally, I have Exclude Mrouter Interface Mode disabled, and as nice as fast leave auto detection would be, I've disabled it because it doesn't seem to be reliable and I only need fast leave on a very small number of select reports.
Also, we are using the switches as switches. I'm pretty sure we don't have any layer 3 features turned on, save for one routing interface we use as a management and monitoring IP. It's possible that using OSPF on the switch itself works and doesn't trigger this problem; I don't know.
Hi rgubele ,
Thanks for your informations.
I think we can do a simple test to verify the cause of the issue.
Case#1: M4300-M4300 [52G/24X stack] <-> [12x12f] --- I've verified that it works
Case#2: Cisco-M4300 --- Could you please verify this case ? (Routing vlan or IP routing interface)
BTW:
For M4300 the MTU was 9198 by default, So It affects protocol message processing with third party devices.
I suggest you try changing the MTU to 1500 on M4300.(Make the MTU of both devices the same)
For VLAN:
(M4300-96X) (Config)#interface vlan 20
(M4300-96X) (Interface vlan 20)#ip mtu 1500For Interface:
(M4300-96X) (Config)#interface 1/1/1
(M4300-96X) (Interface 1/1/1)#mtu 1500Thank you.
Hi kevin_hong ,
The routing table in my environment is too large to enable OSPF on the m4300s, and I don't really have enough spare equipment to lab it out.
I can confirm that Cisco <-> 4300 <-> Cisco doesn't work with IGMP Snooping enabled, as I observed this in my production environment.
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