> Source: [sk115357](https://support.checkpoint.com/results/sk/sk115357)

# sk115357 - "rx_long_length_errors" counter in the output of "ethtool" increases when Jumbo Frames are received on the interface

| Property | Value |
|----------|-------|
| Solution ID | sk115357 |
| Date Created | 2017-01-30 |
| Last Modified | 2017-02-08 |
| Technical Level | General |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- Output of the "`ethtool -S Interface_Name`" shows that "`rx_long_length_errors`" counter increases.

*Example*:

```

[Expert@HostName]# ethtool -S eth1 
NIC statistics:
     ... ...
     rx_long_length_errors: 18
     ... ...
```

## Cause

Jumbo Frames are received on the interface.

Jumbo Frames are Gigabit Ethernet frames of 9000 bytes, but technically this term refers to any frame larger than 1500 bytes.

When Jumbo Frame arrives on the interface with standard MTU (1500), it is dropped at the interface level, and the "**rx_long_length_errors**" counter is increased.

## Solution

Configure the relevant interface with corresponding MTU size that matches the size of the Jumbo frames.

Example for Gaia OS:

1. **HostName\> set interface \<Interface_Name\> mtu \<VALUE\>**
2. **HostName\> save config**

---

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