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Multicast not working between two datacenters

doron.somech
Level 1
Level 1

Multicast is not working between our two datacenter, we have catalyst 2960S (two stacked) as the internal lan switch, and catalyst 3560E as the external switch, same configuration for both datacenters.

The two sites are connected using metro, the external switch (3560) is doing qinq and encapsulate the data from the internal switch with the metro vlan (611).

IGMP snooping is disabled for all switches, although we prefer to enable it for the internal switches.

For each datacenter there is a different firewall which also act as the router, we are using fortigate as the firewall.

Following is the important configuration section:

Port 43 in the internal switch is connected to the external switch (both sites):

interface GigabitEthernet1/0/43

switchport mode trunk

load-interval 30

Port 3 in the external switch connected to the internal switch (both sites):

interface GigabitEthernet0/3

switchport access vlan 611

switchport mode dot1q-tunnel

no cdp enable

no cdp tlv server-location

no cdp tlv app

Port 8 on the external switch connected to the metro link (both sites) vlan 350 is the internet and 611 is the metro:

interface GigabitEthernet0/8

switchport trunk encapsulation dot1q

switchport trunk allowed vlan 350,611

switchport mode trunk

vlan 611 on external switch:

interface Vlan611

ip address 192.168.168.2 255.255.255.0

no ip route-cache

no ip mroute-cache

please help.

Thanks,

Doron

1 Accepted Solution

Accepted Solutions

Ok, Are the Sources and Recievers on the Same VLAN?  Do you have any IGMP Filtering enabled? Do you have any ports on the layer 2 that blocks multicast?

Mohamed

View solution in original post

6 Replies 6

Mohamed Sobair
Level 7
Level 7

Hello,

I am wondering how the Two DataCenters are currently communicating without adding the (Native VLAN) Command on the internal Switch.

Your Internal Switch port 2960, port 43 connected to the external should have the following config on both sides:

interface 1/0/43

switchport mode trunk

switchport trunk encapsulation dot1q

switchport trunk NATIVE VLAN 611

This is the Outer VLAN representing/connecting both sites, and the External Switch should recieve this VLAN-ID untagged from your internal, and then the external Witch TAG it with 611 and tunnel your inner vlans to the other external Switch

do you have a VLAN interface at the other external switch side like (.1)? and can you ping it from (.2) vlan 611 interface

Regards,

Mohamed

Hello,

the 2960 switch doesn't support qinq, 611 is the vlan of the metro, in the internal switch we have other vlans, so the external switch recieving the packewts from the internal switch on port 3 add another tag 611, now the packet is tagged twich, once with the internal switch vlan and once with the 611.

when the information is coming from the metro it goes to port 3 tagged only with the internal vlans.

do you have a VLAN interface at the other external switch side like (.1)? and can you ping it from (.2) vlan 611 interface?

and where do you send the Multicast from and where are the recievers?

Regards,

Mohamed

i have the same vlans at both side, unicast communication is working from site to site.

i tried recievers and senders at both side, none of them worked.

i'm using multicast address

239.162.1.1

Ok, Are the Sources and Recievers on the Same VLAN?  Do you have any IGMP Filtering enabled? Do you have any ports on the layer 2 that blocks multicast?

Mohamed

The correct answer is by mistake.

Yes sources and recievers on the same vlan, no igmp filtering, as far as i know i don't have layer 2 that blocks multicast.

i also suspect that the fortigates may cause the problem, because they send the igmp query, each to his datacenter.

i'm trying to disable the fortigate

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