> Source: [sk181645](https://support.checkpoint.com/results/sk/sk181645)

# sk181645 - ARP requests from the Standby member are sent with VMAC and cause MAC flapping

| Property | Value |
|----------|-------|
| Solution ID | sk181645 |
| Date Created | 2023-11-13 |
| Last Modified | 2023-11-15 |
| Technical Level | General |
| Products | Security Gateway |
| Versions | R81.20, R81.10 (EOS) |
| OS | Gaia |

## Symptoms

- When using [VMAC](https://sc1.checkpoint.com/documents/R81.10/WebAdminGuides/EN/CP_R81.10_ClusterXL_AdminGuide/Topics-CXLG/Configuring-Virtual-MAC.htm?Highlight=vmac), there may be a temporary outage for about a minute without a failover.  
The connection is restored by itself.

## Cause

The Standby member sends ARP requests using the Virtual MAC (VMAC). Consequently, MAC flapping occurs on the Switch, resulting in an outage on the Active member. This occurs because the Virtual IP (VIP) is updated to the Standby member port until a GARP (Gratuitous ARP Requests) is transmitted once more.

## Solution

This problem was fixed. The fix is included starting from:

* [Jumbo Hotfix Accumulator for R81.10](https://sc1.checkpoint.com/documents/Jumbo_HFA/R81.10/Default.htm) starting from Take 128

If you choose not to upgrade, [contact Check Point Support](https://www.checkpoint.com/support-services/contact-support/) to get a Hotfix for your version.

A Support Engineer will make sure the Hotfix is compatible with your environment before providing it.  
For faster resolution and verification, collect [CPinfo](https://support.checkpoint.com/results/sk/sk92739) files from the Management Server and Security Gateways / Cluster Members involved in the case.

**Hotfix installation instructions:**   
Refer to [sk168597 - How to install a Hotfix](https://support.checkpoint.com/results/sk/sk168597).

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