[c-nsp] Cisco 3560G and multicast.

[Xavier Beaudouin]

Hello,

I have a little problem with Cisco 3560G and multicast. I have several
switches connected between and a single VLAN that handle multicast.

I have tried several configuration and it seems that the switch doesn't
filter multicast and give *all* mcast traffic to all ports that are up
and running on the VLAN300.

Here is extract of the configuration :

Current configuration : 4119 bytes
!
! Last configuration change at 11:54:04 EDT Mon Aug 13 2007
! NVRAM config last updated at 11:52:00 EDT Mon Aug 13 2007
!
version 12.2
no service pad
service tcp-keepalives-in
service tcp-keepalives-out
service timestamps debug datetime msec localtime show-timezone
service timestamps log datetime msec localtime show-timezone
service password-encryption
no service dhcp
!
hostname cisco
!
no aaa new-model
clock timezone EDT -5
clock summer-time EDT recurring
system mtu routing 1500
ip subnet-zero
no ip source-route
ip routing
ip domain-name fr.cfm.fr
ip name-server 172.16.0.133
ip name-server 172.16.0.134
!
ip multicast-routing distributed
!
no file verify auto
spanning-tree mode pvst
spanning-tree extend system-id
!
vlan internal allocation policy ascending
vlan dot1q tag native
!
interface GigabitEthernet0/7
 switchport access vlan 300
 switchport mode access
 switchport nonegotiate
 spanning-tree portfast
!
! ...
! all interfaces are configured like this...
!
interface GigabitEthernet0/20
 description To other ciscos...
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 1,2,300,1002-1005
 switchport mode trunk
 switchport nonegotiate
 flowcontrol receive on
!
interface Vlan1
 no ip address
 shutdown
!
interface Vlan2
 description VLAN
 ip address 10.110.100.1 255.255.255.0
 no ip redirects
!
interface Vlan300
 description Back-MCAST
 ip address 10.200.0.101 255.255.255.128
 ip pim sparse-mode
!
ip default-gateway 10.1.3.254
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.3.254
no ip http server
ip http secure-server
!

When looking on usage of mcast groups :

cisco#sh ip igmp groups
IGMP Connected Group Membership
Group Address    Interface                Uptime    Expires   Last
Reporter   Group Accounted
239.1.1.1        Vlan300                  00:39:19  00:02:36 10.200.0.23

239.255.14.1     Vlan300                  00:39:19  00:02:38 10.200.0.36

239.255.14.2     Vlan300                  00:39:19  00:02:42 10.200.0.3

239.255.14.3     Vlan300                  00:39:19  00:02:36 10.200.0.10

239.255.14.5     Vlan300                  00:39:19  00:02:36 10.200.0.22

239.255.14.11    Vlan300                  00:39:18  00:02:40 10.200.0.3

239.255.14.12    Vlan300                  00:39:17  00:02:40 10.200.0.3

239.255.14.13    Vlan300                  00:39:19  00:02:36 10.200.0.25

239.255.13.1     Vlan300                  00:39:19  00:02:36 10.200.0.21

239.255.13.2     Vlan300                  00:39:18  00:02:38 10.200.0.3

239.255.13.3     Vlan300                  00:39:19  00:02:36 10.200.0.28

239.255.13.5     Vlan300                  00:39:19  00:02:36 10.200.0.36

239.255.15.21    Vlan300                  00:39:19  00:02:42 10.200.0.3

239.255.15.1     Vlan300                  00:39:18  00:02:40 10.200.0.27

239.255.15.2     Vlan300                  00:39:19  00:02:40 10.200.0.3

239.255.15.3     Vlan300                  00:39:18  00:02:37 10.200.0.9


Problem is shown there the ip igmp group is handled by the vlan not by
ports (physical ones). Is the any way to make this working correctly on
this material ?

Thanks,
/Xavier