Multicast over split tunnel using Anyconnect client

[christ1111]

Hi Guys,

I have setup a network that uses split tunneling with unicast traffic working as it should where certain traffic is going over the tunnel and other traffic is going outside the tunnel. Multicast also needs to go outside the tunnel.

I can get multicast to work if the AnyConnect client isn't connected, but the multicast stream stops working as soon as the VPN is connected.

I did a Wireshark capture where I can see the IGMP join request is going out the Ethernet port outside the tunnel, but it doesn't join the multicast stream. The Wireshark capture also confirms that the IGMP request is not going inside the tunnel which means the split tunnel is not the issue.

I know in the past that the AnyConnect client drops multicast, but is there any fix/work-around since then?

[Marius Gunnerud]

As far as I know, multicast is still not supported

[christ1111]

Will the AnyConnect client block the multicast even if it is outside the tunnel?

[Marius Gunnerud]

No, if you are running split tunnel multicast should be sent unhindered outside the AnyConnect VPN, that is as long as the multicast traffic is not defined as "interesting traffic"