> Source: [sk179389](https://support.checkpoint.com/results/sk/sk179389)

# sk179389 - Unable to configure MTU on interfaces in a Maestro Security Group after an upgrade from R80.20SP to R81.10 or higher

| Property | Value |
|----------|-------|
| Solution ID | sk179389 |
| Date Created | 2022-06-02 |
| Last Modified | 2023-01-26 |
| Technical Level | Advanced |
| Products | Scalable Platforms |
| Versions | R81.20, R81.10 (EOS) |
| OS | Gaia |

## Symptoms

- * After an upgrade of a Maestro Security Group from R80.20SP to R81.10, MTU on the interfaces has the value of 1500.

* Configuration attempts and their results:

  1. The Gaia gClish command "`set interface <Name of Interface> mtu <Value greater than 1500>`" completes successfully.

  2. Output of the Expert mode command "`cat /config/active | grep mtu`" shows the new configured MTU value.

  3. Outputs of the Expert mode commands "`asg if`" and "`ifconfig`" still show the MTU value 1500.

  4. Output of the "`ifconfig`" command may not show the IP addresses configured on the interfaces.

  5. The Gaia gClish command "`set interface <Name of Interface> mtu 1500`" completes successfully.

  6. Outputs of the Expert mode commands "`asg if`" and "`ifconfig`" show the MTU value 1500.

  7. The Gaia gClish command "`set interface <Name of Interface> mtu <Value greater than 1500>`" now fails with:

     "*Failed to set MTU \<Value\> on interface \<Name of Interface\>. Maximum allowed is 9710*".
     Example: "*Failed to set MTU 9416 on interface eth2-05. Maximum allowed is 9710*"
  8. For the interfaces BPEth0 and BPEth1, the output of the Expert mode command "`cat /config/active | grep mtu`" shows the MTU value greater than 9710.

## Cause

In the previous version R80.20SP, the configured MTU value was greater than 9710 (for example, 10240).

Starting in the version R81.10, the maximum allowed MTU value is 9710.

## Solution

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

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