> Source: [sk106777](https://support.checkpoint.com/results/sk/sk106777)

# sk106777 - Adding a new VLAN with highest VLAN ID causes the Virtual System to go "Down"

| Property | Value |
|----------|-------|
| Solution ID | sk106777 |
| Date Created | 2015-07-08 |
| Last Modified | 2015-12-31 |
| Technical Level | Advanced |
| Products | Security Gateway, Hardware |
| Versions | R82.10, R82, R81.20, Not Version-Specific |
| OS | Gaia |
| Platform | 3000 |

## Symptoms

- * State of Virtual System in VSX High Availability cluster 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. VLAN with lowest VLAN ID was configured on one Virtual System "A" ("VS_A")
  3. VLAN with highest VLAN ID was configured on another Virtual System ("VS_B")
  4. VLAN was configured on Virtual System "A" ("VS_A") with VLAN ID, which is higher than any existing VLAN ID on Virtual System "B" ("VS_B")
* Output of "*cphaprob -a if*" command shows that all cluster interfaces are "UP", but the number of "Required interfaces:" is larger than it should be.

* Rebooting the VSX cluster member resolves the issue.

## Cause

In some scenarios, changing the VLAN configuration in SmartDashboard might cause the number of "Required interfaces:" to be incorrect (refer to the output of "*cphaprob -a if*" command).

Critical Device "Interface Active Check" reports its status as "problem" because the number of required interface is not reduced correctly when an interface becomes a non-monitored interface.

## Solution

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

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