RG-NBS3100-24GT4SFP-P management issue

Hi;
We are using a ruijie nbs3100 model switch. Software version ReyeeOS 2.320.0.222
When we make the uplink port one of the sfp ports, we cannot connect to the management interface of the switch. When we make one of the copper ports an uplink, we connect without any problems. What could be the problem?

Hello Ahmet

you can start checking this :

1. SFP Port Not in the Same VLAN / Management VLAN Not Tagged

The SFP port may not be configured to carry the management VLAN (typically VLAN 1 or a custom one).
Fix
Check the VLAN configuration on the SFP uplink port.
If your management interface is on VLAN 1 (or another VLAN), ensure that:
The SFP port is set to [strong]trunk[/strong] mode (if multiple VLANs need to pass).
The correct VLAN is [strong]tagged[/strong] or [strong]untagged[/strong] appropriately depending on the upstream switch/router.

2. Port Mode Mismatch (Access vs Trunk)

If the SFP port is in access mode and the upstream device is sending tagged frames, or vice versa, communication breaks.
Fix

• Match the port mode with the upstream device (trunk ↔ trunk, access ↔ access).
• If trunking, make sure the management VLAN is allowed on the trunk.
  

3. STP (Spanning Tree Protocol) Blocking

If STP is enabled, the SFP port might be in a blocking  or listening state.
Fix

• Check STP status for that port.
• Look in the switch logs for STP-related messages.
• Temporarily disable STP for testing (not recommended for production).
  

4. SFP Module Compatibility

Some switches are picky about SFP modules (especially with third-party or "non-OEM" ones).
fix
Verify that the SFP module you're using is Ruijie-certified  or explicitly compatible with the NBS3100.
Try swapping with a known-good SFP module.

5. Incorrect or Missing IP Address / Default Gateway

The switch may not have a proper default gateway or IP address configuration when using the SFP uplink.
Fix

• Confirm the management VLAN interface has a valid IP and default gateway.
• Ping the gateway from the switch’s CLI if available.
  

6. [strong]Link Comes Up But No Traffic[/strong]

Duplex mismatch or auto-negotiation issues.
Fix
Check speed/duplex settings on both the SFP port and the connected device.
Manually set both to [strong]1G/full[/strong] if supported.
Also if you try another SFP port and it works this port may be damaged