> Source: [sk115852](https://support.checkpoint.com/results/sk/sk115852)

# sk115852 - Security Gateway with PIM Sparse-Mode registers multicast traffic for non-local subnets

| Property | Value |
|----------|-------|
| Solution ID | sk115852 |
| Date Created | 2017-02-14 |
| Last Modified | 2017-06-18 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- * Output of the Gaia Clish command "`show pim joins`" shows that the Security Gateway registers the multicast source even if the Multicast Source does not match the Security Gateway's interfaces subnets.

  *Example*:
  `(<Multicast_Source>, <Multicast_Group>), 00:36:46/13:28:22, RP: <Rendezvous_Point_IP_address>`  
  `
  Flags: T|M|A|E`  
  `
  `**Register source: <Security_Gateway_IP_address>, Register destination: <Rendezvous_Point_IP_address>**   
  `
  Incoming interface: Eth-<x>, RPF neighbor: <Downstream_Multicast_Neighbor>`  
  `
  Outgoing interface list:`  
  `
  Eth-y, 00:36:46/13:28:22`
* Output of the Expert mode command "`ip mroute`" shows in the list of outbound interfaces "`Oifs`" both "`pimreg0`" and the physical interface facing the Multicast client.

  *Example*:
  `[Expert@HostName:0]# ip mroute `  
  `
  (<Multicast_Source>, <Multicast_Group>) Iif: Eth-<x> Oifs: `**pimreg0**` Eth-<y>`
* If the Rendezvous Point replies with a "register-stop", then the Security Gateway will continue sending "null-register" messages to the Rendezvous Point every 60 seconds.

## Cause

The Security Gateway does not check whether the Multicast Source is a local subnet before registering the Multicast Group to the Rendezvous Point.

## Solution

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