Problem with bonded Ethernet NICs and wireless access points

DarfNader Member Posts: 3
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I have some devices like two network file servers which I have set up bonded Ethernet for better network throughput. The problem is the Fing doesn’t seem to understand this. It sees two identical devices which would appear to swap ownership of their IP where the device that has no IP is “in range” at that time. Neither device appears “dominant”. The problem with this is that I want Fing to notify me if this host goes offline, but since it flaps between seeing these two NICs of he bonded pair it will be just constantly floods you with alerts.
I suspect the simple reason for this is that the bonded pair doesn’t share a single MAC ID so Fing is confused.
A similar thing happens with my remote mesh access point where it sees the device as having two MAC IDs which I presume is for the Ethernet NIC and the wireless NIC which seems stuck in range.
I see similar aberrant behavior with multi-homed hosts even where each NIC has its own IP where both NICs are shown to share an IP which is erroneous. This is the case with a ThinkCenter running Ubuntu 18 with both an Ethernet and wireless NIC where each has its own IP. Fing shows it having two IPs on the Ethernet NIC which is just wrong.
Anyone else see this? Is this just a shortcoming of Fing and/or is there some kind of workaround?


  • Marc
    Marc Moderator, Beta Tester Posts: 3,158
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    @DarfNader I'm thinking this is a shortcoming of Fing as you identified in the other scenarios mentioned.  @Robin , could you verify that this is a known behavioral shortcoming and whether you have any suggestions for a workaround or if one is even possible?  Maybe this could go in as a feature request?
    Thats Daphnee, she's a good dog...
  • Mirekmal
    Mirekmal Member, Beta Tester Posts: 69
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    Well, depending on devices that use bonded connection you might see different behaviousr. In some cases 2 connections that form bond will be seen as 2 separate devices with separate MACs, most likely one of them being active and one in range, sometimes bonded connection will create additional, virtual MAC for bond and forming interfaces will be seen as in range. I have similar case for 'storage' VLAN - I have Synology NAS connected using bonded interfaces with (well, with switch in between also used for other 'user' connections) to my ESX server. These connectons are on separate VLAN, using different subnet, yet visible to fing, always in range... I just got used to this...
  • Robin_Ex_Fing
    Robin_Ex_Fing Member Posts: 5,293
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    Hi @DarfNader
    First of all, please make sure all ports needed for Fingbox is open for it. Ports 80, 443 are usually used by Synology NAS.  You will need to change those port configurations so that both of these devices can work together.  
    This is just a sample from WD on how to do this.  This is from their community forum.

    The Fing App discovery will identify devices on a best effort basis, based on the information made available by the device, e.g. the MAC address. In your case, Fing App will recognize each NIC card as separate as their MAC address with each NIC will be different. As of now, there is no way to group separate identified devices together. 
    Robin (Admin at Fing)
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  • Systops
    Systops Member Posts: 6
    First Comment
    Can I please clarify something? Which Synology NAS does the OP have? When you say that you are using a bonded connection, are you using a Synology NAS Server which has 2 Network Adapters? Are you running in a LAG Configuration (which creates a Bonded Adapter, however, each NIC should have it's own MAC Address and an independent IP Address for each NIC regardless if you are using a Bonded Connection. This would explain why you would see two very similar (identical expect for the MAC and IP Addresses). I am having a similar issue, which sounds like the issue I am coming across, however, in my case, my NAS server does have two NIC' in a LAG /  Bonded Connection.