> Source: [sk112116](https://support.checkpoint.com/results/sk/sk112116)

# sk112116 - Gratuitous ARP requests are seen on VLAN not configured for Proxy ARP

| Property | Value |
|----------|-------|
| Solution ID | sk112116 |
| Date Created | 2016-12-12 |
| Last Modified | 2018-11-18 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- * Proxy ARP is configured for a specific VLAN (Example eth3.100):  
  * Sample configuration from clish on Gateway:
    * `add arp proxy ipv4-address 200.1.1.10 interface eth3.100 real-ipv4-address 200.1.1.1`
    * `add arp proxy ipv4-address 200.1.1.15 interface eth3.100 real-ipv4-address 200.1.1.1`
    * `add arp proxy ipv4-address 200.1.1.20 interface eth3.100 real-ipv4-address 200.1.1.1`

    <br />

    <br />

  * When a tcpdump is run on another VLAN associated with the same physical interface (Example Eth3.200), gratuitous ARP (GARP) requests for the proxied IP's are seen:

    * `#tcpdump -nei eth3.200 arp`
    * `arp who-has 200.1.1.15 tell 200.1.1.15`
    * `arp who-has 200.1.1.10 tell 200.1.1.10`
    * `arp who-has 200.1.1.20 tell 200.1.1.20`

## Solution

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