Bpi r2 pro use lan ports in same subnet

Hello I have a BPI R2 PRO and I use ( [BPI-R2 Pro] Debian Bullseye / Ubuntu 22.04 I want to give static IPs to lan ports in the same subnet when I did it I could not get ping request . Is there any way for this problem? Best Regards

In order to have all (some) lan ports in a single subnet, You have to create a bridge and add all required lan-ports to it.

In general R2 Pro approach should be the same as for R2, since both of them uses the same dsa-driver.

So you may starrt with this thread.

Hello thanks for your reply but i want to assign lan ports different ips in same subnet Best Regards

That’s not possible because routing requires to have 1 interface per subnet

Hello, Are arp_announce=1 and arp_ignore=2 commands helpful for this purpose? Or there is no hope

Best regards

The task is not really clear, at least for me. Are you going to assign a multiple ip addresses from a same subnet for different LAN ports?

In general it might be possible when you use policy based routing. As i got it’s not a R2 PRO related, but a general Linux related task. But no useful advice beyond “policy based routing” and probably “ip unnumbered” keywords unless the task is clear. :wink:

Thank you . Now I want to assign different ip in same subnet for example lan ports lan0->,lan1->, I will research on this problem, when I found solution i will post here

The question is why do you need different ips from same subnet on same device?

You can work over a bidge with 1 ip and still monitor traffic on port. It will be more performant using bridge than do all with (policy) routing.

I have not used policy routing this way, as this looks like a horrible setup where it can be better ways.

i used it for routing packets from specific interface,my voip pppoe, to specific device, my voip box. And some time ago i did some kind of loadbalancing over 2 uplinks which needed policy routing too (and marking in firewall).

Hello, I have 4 TCP-based devices and their IPs are static, end they send HL7 information through TCP. They were on the same network and their destination IP was static I can’t change it because I don’t know their password. Now I have destination IPs and devices’ IPs, I want to assign their destination IPs to plan ports. But When I set the same Ip in the same subnet it not working. I tried ar_filter and I thought it worked. But I am wrong It is not working.

if you have a birdge with ip from same subnet you can access all 4 devices…but you cannot use one of the ip’s these external devices using. you don’t need to set ip on each lan-port


Thank you for your reply but all of 4 devices first connect to BPI R2 pro , after connecttion they send data to lan ports I can not need send data to devices . They send data in one-direction. I listening TCP/IP data which come from devices. I could not acces the IP configuration of devices . Because their configuration password lost long time ago.

nearly all devices have a factory-reset function to reset them to the vendors defaults

I read some articles about this problem which callad ARP Flux avoiding . I am not sure but there is a interesting thing happened. my lan2 ->> my lan3->> external devices on When I plug my etehernet cable on lan2 I used and I saw I can send ping from lan2 with IP of LAN3 ping -I

I am not sure but I think in restarting of networking process something going wrong and lan3 interfaces could start properly. Could you share resaon of this problem ? Best regards

it is the routing problem i mentioned…if you have multiple interfaces with same ip subnet, routing process does not know to which interface it should send the data when only using the target-ip…you can define also device for ping, but you cannot do normal traffic without very complex setup…

maybe using a bridge and assigning all ips you currently want on the lan-interfaces??

a single interface can handle multiple IPs from same subnet…

Could you give more details please? Best Regards.

if i understand you correctly your devices in same subnet sending data to a specific IP which you try to assign to your lan-ports.

so you can create a bridge and then add all the local target-ips to the bridge (do not know if this can be done via interfaces-file)

ip a a dev br0
ip a a dev br0

this results in clear routing where the subnet is only on the bridge configured and all devices can send data to the specific ip which is always on the bridge

edit: this way you can do it in interfaces-file (if openwrt supports this override-syntax):