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If you ping the devices IP from a PC, then display the PC arp cache [command: arp -a] you should see the correct entry.
I suggest that the router is only using part of the Host ID. You could try changing the host ID on the device to see if it makes any difference.
That is very strange indeed. Does the DHCP table show the same? What are the MAC addresses printed on the devices you mention?
GrahamRHK – 7 hours ago »
That is very strange indeed. Does the DHCP table show the same? What are the MAC addresses printed on the devices you mention?
While some hosts may allow the MAC address to be changed the MAC address is used to communicate on the subnet and is designed to be unique.
I think this is a clear router display bug.
Quote:While some hosts may allow the MAC address to be changed the MAC address is used to communicate on the subnet and is designed to be unique.This is certainly true of PCs – in Windows it is relatively straightforward to change the MAC address. However this requires root or superuser privileges. That would be almost impossible with streaming devices and TVs etc as these are locked down. I have read that Android devices may be more amenable to MAC address change but it is very strange that all the devices mentioned should have the same address unless someone did it deliberately. I have the same router as the post originator and both the ARP cache table and DHCP table show unique MAC addresses across about 15 devices. And one should say also that if the router has many devices with the same MAC address, performance will be terrible even if it works at all. Intriguing problem! Would be useful to know the MAC addresses printed on the device labels.
I would lay quite a lot of money of the labels all having different MAC addresses.
Some Routers allow changing the MAC address on the WAN so that they can replace a ISP supplied modem which uses the MAC address to sign-in the user.
One question I ask is are both your routers on the same firmware release?
GrahamRHK – 1 day ago »
That is very strange indeed. Does the DHCP table show the same? What are the MAC addresses printed on the devices you mention?
Good question – answer is No!
Every MAC address on the DHCP table is unique and different, whilst the ARP table continues to show six IP addresses all showing the exact same MAC address.
I don’t even Draytek know why. They’ve asked me to reboot the router a number of times and provide screenshots of the ARP table, and it’s the same every time…
Quote:Every MAC address on the DHCP table is unique and differentIn that case you don’t have a problem doing what you want to do – bind IP to MAC to allow you to set the correct entries in the routing table to determine which devices use the VPN and which use the WAN directly.
Quote:ARP table continues to show six IP addresses all showing the exact same MAC addressI see from your screen shot that all these devices are on port S1 – the Draytek inbuilt wireless. Do you have a wireless repeater, perhaps connected via a network hub, in the mix somewhere? My hunch is that the MAC address that seems to be associated with multiple devices in the ARP cache is in fact a hub or wireless AP. The labels printed on the devices should confirm or otherwise.
Quote:One question I ask is are both your routers on the same firmware release?Mine is 3.9.1.3_BT FYI
GrahamRHK – 3 days ago »
Quote:I see from your screen shot that all these devices are on port S1 – the Draytek inbuilt wireless. Do you have a wireless repeater, perhaps connected via a network hub, in the mix somewhere? My hunch is that the MAC address that seems to be associated with multiple devices in the ARP cache is in fact a hub or wireless AP. The labels printed on the devices should confirm or otherwise.
A good shout – I do have an AP900 repeater to extend the signal. I got some assistance with Draytek to set it up, so that it doesn’t actually appear as a “separate network” and actually provides a seamless, invisible extension of the wireless networks. It looks like the devices that are attached the repeater are showing on the router in this way for this reason. Draytek have asked me to contact them, so it appears that this wasn’t particularly obvious to them!
Quote:One question I ask is are both your routers on the same firmware release?Mine is 3.9.1.3_BT FYI
Mine is running 3.8.9.7_BT – which I’ve just checked is the latest firmware for this router. It’s always the first thing Draytek check too whenever you get a bit of remote support from them…
Quote:Mine is running 3.8.9.7_BTIt is odd that you say that. I have just checked Draytek UK website and the latest firmware is 3.9.2. The release notes say this is optional when convenient. It was released on 23 January 2020. So mine is back level too – but I am leaving well alone for now!
Quote:provides a seamless, invisible extension of the wireless networksIt would be interesting – when you have a moment – to check the MAC address label printed on the AP900.
Quote:It would be interesting – when you have a moment – to check the MAC address label printed on the AP900.The reason I ask this is that, having confirmed you have a wireless repeater, I understand that these repeaters can hide the MAC addresses of connected devices behind their own when receiving ARP requests. i.e. when the router broadcasts “who has got 192.168.1.nn” the repeater responds with its own MAC address. I am learning all the time! I have yet to understand why it works this way.
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