> Source: [sk179984](https://support.checkpoint.com/results/sk/sk179984)

# sk179984 - Cannot increase the MTU value of a bonded tagged interface

| Property | Value |
|----------|-------|
| Solution ID | sk179984 |
| Date Created | 2022-09-20 |
| Last Modified | 2023-08-07 |
| Technical Level | General |
| Products | Scalable Platforms |
| Versions | R81.10 (EOS) |

## Symptoms

- When you increase the MTU of the bonded tagged interface through the Virtual System (VS) object in SmartConsole:  

* "`ifconfig`" shows that the MTU of the trunk interface changed successfully:
  * `bond0 Link encap:Ethernet HWaddr 00:1C:7F:81:05:07`  
    `UP BROADCAST RUNNING MASTER MULTICAST `**MTU:9000**` Metric:1`

<!-- -->

* "`ifconfig`" shows that the MTU of the bonded tagged interface did not change:
  * `bond0.550 Link encap:Ethernet HWaddr 00:1C:7F:81:05:07`  
    `inet addr:192.168.2.2 Bcast:192.168.2.255 Mask:255.255.255.0`  
    `UP BROADCAST RUNNING MULTICAST `**MTU:1500**` Metric:`
* "`vsx showncs`" shows that the configuration was pushed successfully to the VS.

<br />

## Cause

A known issue causes the default values for the MTU to be pushed again after you push the VS configuration from SmartConsole.

## Solution

This problem was fixed. The fix is included in:

* [Jumbo Hotfix Accumulator for R81.10](https://sc1.checkpoint.com/documents/Jumbo_HFA/R81.10/Default.htm) starting from Take 110
* [Jumbo Hotfix Accumulator for R81](https://sc1.checkpoint.com/documents/Jumbo_HFA/R81/Default.htm) starting from Take 87

If you choose not to upgrade, this **workaround** is available:   

Change the MTU of the bonded tagged interface:

1. Increase the value of the MTU to a larger value than that of the default value.
   * **Example**: If the default value is 1500, select a value that is larger than 1500.
2. Increase the MTU a second time to a value that is smaller than the selected MTU value.
   * **Example**: If the selected value is 2000, select a value that is smaller than 2000.
3. Select the desired MTU.

<br />

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