> Source: [sk168879](https://support.checkpoint.com/results/sk/sk168879)

# sk168879 - Interface speed and duplex shows as "Unknown!"

| Property | Value |
|----------|-------|
| Solution ID | sk168879 |
| Date Created | 2020-08-31 |
| Last Modified | 2021-09-22 |
| Technical Level | General |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- * Interface speed and duplex shows as unknown when running ethtool:

  ```
  
  [Expert@GW:0]# ethtool eth1-01
  Settings for eth1-01:
          Supported ports: [ FIBRE ]
          Supported link modes:   1000baseT/Full
                                 10000baseT/Full
          Supports auto-negotiation: Yes
          Advertised link modes:  1000baseT/Full
                                  10000baseT/Full
          Advertised auto-negotiation: Yes
          Speed: Unknown! ***
          Duplex: Unknown! (255) ***
          Port: FIBRE
          PHYAD: 0
          Transceiver: external
          Auto-negotiation: on
          Supports Wake-on: d
          Wake-on: d
          Current message level: 0x00000007 (7)
          Link detected: no
  ```

  <br />

* Althogh the interface is up, no traffic passes through it.

* Reboot of the Security Gateway does not resolve the issue.

* Running command "ip link show" provides a "NO CARRIER" error:

  ```
  
  [Expert@FW:0]# ip link show
  1: eth1-01:  mtu 1500 qdisc pfifo_fast qlen 1000 ***
      link/ether 00:1c:7f:68:8e:f2 brd ff:ff:ff:ff:ff:ff
  2: eth1-02:  mtu 1500 qdisc pfifo_fast qlen 1000 ***
      link/ether 00:1c:7f:68:8e:f3 brd ff:ff:ff:ff:ff:ff
  3: eth1-03:  mtu 1500 qdisc pfifo_fast qlen 1000 ***
      link/ether 00:1c:7f:68:8e:f4 brd ff:ff:ff:ff:ff:ff
  ```

  <br />

* The proper SFP modules that came with the gateway are used to install the fiber lines.

## Cause

Physical link is down.  
"Link detected: **no"**As long as the link state is down, the link speed and duplex cannot be determined and will be presented as "unknown!"

## Solution

This is not a Check Point issue.  

Make sure that the connecting device (be it a switch or router) is using the proper SFP module, and that there is a proper connection .

---

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