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SPS2024 and IGMP issues


I have have issues with using mutlicast stream with this device with following configuration:

[ Uplink/Internet ] ------L3_link------- eth0_[ router (linux + PIM daemon)]_eth1 ====trunk==== g1_[ SPS2024 ]_g2 ----access---- PC

- there is router on stick configuration between router and switch with following details:

eth1 (without IP address) <====> Unused VLAN (VLAN500)

eth1.10 <====> VLAN10

eth1.11 <====> VLAN11

eth1.12 <====> VLAN12

- router is PIMv2 (in PIM-SM mode) and IGMPv2 capable router and it periodically sends IGMP queries into all three VLANS (10, 11, 12)

And the main issue is, that computers connected to any VLAN are NOT receiving IGMP queries packets.


- I can see via tcpdump that igmp are periodically sent to all three (sub)interfaces eth1.10, eth1.11 and eth1.12

- there is no firewall access rule on outgoing interfaces  (there is permit all outgoing)

- when I run wireshark on comuters from any VLAN, I can't see multicasted IGMP queries

- only IGMP traffic that I can see are IGMP report packets

- situation is same when IGMP snooping is or is NOT enabled on VLAN interface or globally (...igmp snooping feature makes not any difference in this behavior)

- here are some outputs:

dist-sw# sh ip igmp snooping interface 10   <<<<<<<< same output for all three VLANs

IGMP Snooping is globaly enabled

IGMP Snooping is enabled on VLAN 10

IGMP Snooping admin: enabled

Routers IGMP version: 0

Groups that are in IGMP version 2 compatibility mode:

Groups that are in IGMP version 1 compatibility mode:

IGMP snooping querier admin: disabled

IGMP snooping querier oper: disabled

IGMP snooping querier address admin:

IGMP snooping querier address oper:  <<<<<< management IP address of this switch

IGMP snooping querier admin version: 0

IGMP host timeout is 260 sec

IGMP Immediate leave is disabled. IGMP leave timeout is 10 sec

IGMP mrouter timeout is 300 sec

Automatic learning of multicast router ports is enabled

dist-sw# show ip igmp snooping mrouter interface 10

VLAN              Ports

-------           ----------------------------------------

Detected multicast routers that are forbidden statically:

VLAN              Ports

-------           ----------------------------------------

so in real, mutlicast service is completely broken in this scenario.

Working scenario 2:

[ Uplink/Internet ] ------L3_link------- eth0_[ router (linux + PIM daemon)]_eth2 ----access---- g3_[ SPS2024 ]_g4 ----access---- PC

In this scenario there is access link between router and SPS2024 switch which carries frames from single subnet/VLAN.

In this scenario:

- I can see IGMP queries via wireshark on PC connected to port g4

- and multicasts are completely working  as expected

- it is working regardless IGMP Snooping is enabled (on VLAN and globally) or not

- BUT outputs from switch CLI are completely same as from first scenario (switch not recognized any IGMP querier on segment, nor PIMv4 packets (for determining mrouter port) ( case when IGMP snooping was enabled)

In summary:

- this looks like this switch is not able to forward igmp queries in case when they comes from tagged VLANs via trunk port

- switch is also not able to recognize mrouter nor igmp querier on segment (according outputs above)

And finally questions:

- is this correct behavior of this switch?

- how can I fix it? I am using latest firmware 1.0.6, but this is same also with older version 1.0.2

- are there any debug commands available (to see packets receiving, igmp snooping working and so on) like from Catalyst switches?

Many thanks for any help

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