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DHCP Snooping cannot be enabled on port

DHCP Snooping cannot be enabled on port

DHCP Snooping cannot be enabled on port
DHCP Snooping cannot be enabled on port
a week ago - last edited Friday
Tags: #DHCP Service
Model: SG2218P  
Hardware Version: V2
Firmware Version: 2.0.14 Build 20260121 Rel.53429

Hello, I am new to the DAI/DHCP Snooping feature. I am having issues trying to enable DHCP snooping on my ports. I understand that it cannot be enabled on uplink/downlink ports but most of these ports are configured as access ports, why can't I select them?

 

Thank you for your help!

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#1
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6 Reply
Re:DHCP Snooping cannot be enabled on port
a week ago - last edited Friday

Hi  @zacl 

Please refer to this guide for more information and make sure the Controller version of yours is 6.1 or above.

If the issue still persists, please provide us with the network topology as well as the error.

Best Regards! >> Omada EAP Firmware Trial Available Here << >> Get the Latest Omada SDN Controller Releases Here << *Try filtering posts on each forum by Label of [Early Access]*
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#2
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Re:DHCP Snooping cannot be enabled on port
a week ago
Hi @Hank21, I am using Controller v6.1.0.19 and I had followed the guide. However, I cannot select any of the connected ports. As you can see in my 2 screenshots, even ports going to APs or IPCs cannot be snooped. Why is that the case?
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#3
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Re:DHCP Snooping cannot be enabled on port
a week ago

Hi  @zacl 

It is noticed that your SG2218P V2 has a newer firmware version, please try  to update this 2.0.17 and try to configure the DHCP snooping again.

If this still cannot work, please provide us the network topology and tell us what devices connected to the switch.

Best Regards! >> Omada EAP Firmware Trial Available Here << >> Get the Latest Omada SDN Controller Releases Here << *Try filtering posts on each forum by Label of [Early Access]*
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#4
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Re:DHCP Snooping cannot be enabled on port
Monday

@Hank21 I have updated the switch to new 2.0.17 firmware already, but the issue still persists. As requested, network topology and connected devices as follows (it is same as the port view that I showed above):



As you can observe from my initial screenshot, all connected ports cannot be snooped; only unconnected ports can be selected.

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#5
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Re:DHCP Snooping cannot be enabled on port
Friday

  @zacl 

 

You can only enable snooping on ports that dont go to devices that the controller recognises as a SDN or ViGi device.

 

I just checked and i cannot enable it for things like my ViGi cameras (recognised as a "downlinked" device and EAPs

 

This could be intentional, or a bug, not sure

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#6
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Re:DHCP Snooping cannot be enabled on port
Friday

@GRL Thanks for sharing! In my case, all of the connected devices (APs, NVRs, IPCs) cannot be enabled. I can understand if uplink ports are disabled but cannot understand why they are disabled for downlink ports?

 

Based on the documentation:

Choose the ports you wish to enable DHCP Snooping on, by choosing a port, the DHCP packets will be snooped to form IMPB entries, and the DHCP server response packets sent from the client connected will be dropped.


It does look like a bug to me unless I am misunderstanding this?

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#7
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