> Source: [sk180930](https://support.checkpoint.com/results/sk/sk180930)

# sk180930 - Traffic is dropped with the reason "bridge - xmt ifn is same as rcv ifn"

| Property | Value |
|----------|-------|
| Solution ID | sk180930 |
| Date Created | 2023-05-09 |
| Last Modified | 2023-07-12 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R81.20, R81.10 (EOS), R81 (EOS) |
| OS | Gaia |

## Symptoms

- * The traffic is received through the same interface it was transmitted from, and then dropped on the Security Gateway. <br />

* The `fw ctl zdebug + drop` command shows these messages:   
  `
  prepare_cut_through: bridge - xmt ifn is same as rcv ifn (X), conn: <src_ip,sport,dst_ip,dport,proto>;`  
  `
  sim_pkt_send_drop_notification: (1,0) received drop, reason: Interface Down, conn: <src_ip,sport,dst_ip,dport,proto>;`  
  `
  sim_pkt_send_drop_notification: no track is needed for this drop - not sending a notificaion, conn: <src_ip,sport,dst_ip,dport,proto>;`  
  `
  do_packet_finish: SIMPKT_IN_DROP vsid=1, conn: <src_ip,sport,dst_ip,dport,proto>;
  `

  <br />

## Cause

SecureXL checks and drops traffic that enters the Security Gateway through the same interface from which the traffic left the Security Gateway. SecureXL does this to prevent the traffic from passing through the Security Gateway two times.

## Solution

This solution requires authentication. Please log in to view the full solution.

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