> Source: [sk106776](https://support.checkpoint.com/results/sk/sk106776)

# sk106776 - Adding a new VLAN with lowest/highest VLAN ID causes the ClusterXL member to go "Down"

| Property | Value |
|----------|-------|
| Solution ID | sk106776 |
| Date Created | 2015-07-08 |
| Last Modified | 2019-11-18 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- * State of ClusterXL member changes to "Down" due to Critical Device "Interface Active Check" in the following scenario:

  1. Monitoring of the lowest and highest VLANs is enabled (default; *fwha_monitor_low_high_vlans=1*)
  2. A new VLAN is added on the ClusterXL member with VLAN ID, which is lower/higher than any existing VLAN ID (Note: It does not matter if the new VLAN is configured on the switch)
* After fetching the new topology in SmartDashboard and installing the policy on the cluster, state of this ClusterXL member changes to an expected "Active" / "Standby".

* Additional possible symptom: Only lowest VLAN is monitored on Bond interface, instead of lowest and highest:

  1. VLAN interfaces were defined on Bond interface
  2. Value of kernel parameter *fwha_monitor_low_high_vlans* is 1 (default; refer to [sk92826](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk92826))
  3. If CCP packets are not able to pass on the *highest* VLAN, Bond interface is *not* declared as "down" by the cluster member
  4. If CCP packets are not able to pass on the *lowest* VLAN, Bond interface is declared as "down" by the cluster member as expected

## Cause

1. Issue 01415023: ClusterXL member is updated about the newly added or removed VLAN immediately, which causes a mismatch between the local configuration and the cluster configuration installed by the policy.
2. Issue 01987109: The kernel parameter *fwha_update_monitored_vlans* is not applied to Bond interfaces.

## Solution

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