> Source: [sk173976](https://support.checkpoint.com/results/sk/sk173976)

# sk173976 - Multicast Passthrough traffic does not leave the gateway after upgrade to the 3.10 kernel on a Bridge interface

| Property | Value |
|----------|-------|
| Solution ID | sk173976 |
| Date Created | 2021-06-18 |
| Last Modified | 2023-12-19 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R81.10 (EOS) |
| OS | Gaia |

## Symptoms

- * After upgrading to the 3.10 kernel multicast no longer passes the gateway
* The same configuration works fine on the 2.6.18 kernel
* Bridge interfaces are in use for the traffic

## Cause

After upgrading to the 3.10 kernel a new parameter was introduced in order to control Multicast Snooping on Bridge interfaces. This parameter multicast_snooping is enabled by default and causes multicast packets that the gateway is only passing (not participating) to be dropped on the bridge itself.

## Solution

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