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TL-ER7206: Detected ARP conflict

sagar002100

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2024-01-01 11:26:51

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Registered: 2020-06-06

TL-ER7206: Detected ARP conflict

2024-01-01 11:26:51

Model: ER7206 (TL-ER7206)

Hardware Version: V1

Firmware Version: 1.2.3 Build 20221104 Rel.41500

Hello Everyone,

Happy new year...!!!

We are facing a weird issue in our network. We are using TL-ER7206 as our Internet gateway router, it's LAN ip address is 172.21.21.21/16.

DHCP range is from 172.21.8.1 to 172.21.9.255.

We have reserved IP address from 172.21.6.1 to 172.21.6.100 for computers and laptops in our network.

Since yesterday, network went down suddenly and when we check log in the router, we found a WARNING message stating "Detected suspected ARP attack packets. Be careful! ".

We are receiving this message periodically, " [osg:78-8C-B5-7D-40-B4] detected ARP conflict and dropped 1 packets. (Packet=172.21.21.21:46-01-BB-0C-30-16, Bind-Rule=172.21.21.21:78-8C-B5-7D-40-B4) "

Router LAN IP= 172.21.21.21

Router LAN MAC= 78-8C-B5-7D-40-B4

When we tried to lookup 46-01-BB-0C-30-16 MAC address for the its vendor/OUI, it is showing UNKNOWN.

So as of now network is not stable, ping is dropped to the devices in the LAN.

Please help and guide me to trace this issue.

With regards,
Sagar Patel

1 Reply

Clive_A

2024-01-02 03:04:11

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Registered: 2023-06-09

Re:TL-ER7206: Detected ARP conflict

2024-01-02 03:04:11

Hi @sagar002100

Thanks for posting in our business forum.

Unfortunately, there is no best way to get this resolved.

First, this is an unknown MAC address, so it might be a virtual MAC. There seems to be a person who's trying to replace the legal DHCP server.

So, you should set up the legal DHCP server to avoid any loss.

But eventually, you should find out the person who's trying to replace the legal DHCP server with his illegal one.

This part is beyond our support range. It's more like network security. About this, you can probably find out the way to trace it down by Google-ing it.

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sagar002100

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2024-01-01 11:26:51

Posts: 24

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Registered: 2020-06-06

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