WR802Nv1 no ARP Reply for some MAC-Adresses

This thread has been locked for further replies. You can start a new thread to share your ideas or ask questions.

WR802Nv1 no ARP Reply for some MAC-Adresses

This thread has been locked for further replies. You can start a new thread to share your ideas or ask questions.
WR802Nv1 no ARP Reply for some MAC-Adresses
WR802Nv1 no ARP Reply for some MAC-Adresses
2018-07-10 22:15:55
Model : TL-WR802N

Hardware Version :

Firmware Version : 3.16.9 Build 150717 Rel.48906n

ISP :

Hello,

we have at the moment 25x WR802N "on the road". We use them in various combinations with different access points. But sometimes we have "strange” problems.


We did some testing in our testlab and get following results:

Test environment:
· Dell Laptop (Windows 10) connected to layer 2 switch
· Fujitsu Siemens desktop pc (Debian Linux) connected layer 2 switch

· WLAN Access point connected layer 2 switch
· 1x TP-Link WR802n at client mode connected via WPA2 WLAN to the access point

Test procedure:
· Ping from Laptop (172.16.1.99/24) to management IP from WRN802n (172.16.1.169/24) = successful
· Ping from Laptop (172.16.1.99/24) to another laptop (172.16.1.19/24) behind the WRN802n = successful
· Ping from desktop pc (172.16.1.254/24) to management IP from WRN802n (172.16.1.169/24) = not possible
· Ping from desktop pc (172.16.1.254/24) to another laptop (172.16.1.19/24) behind the WRN802n = not possible

After checking all the firewalls, ipconfigs etc. we did a port mirroring on the layer 2 switch and record all the packets coming from directly from the access point via Wireshark.

Results/findings:
· The WRN802n does gratuitous arp. This is not written in the manual!
· If the dell laptop is doing an arp request for 172.16.1.19 or 172.16.1.169 the WRN802n is replying as expected with an arp reply and his MAC address (f4:f2:6d:b9:72:4c). Everything fine.
· If the desktop client (MAC address 00:01:80:7a:bf:d6) is doing an arp request for 172.16.1.19 or 172.16.1.169 the WRN802n is NOT replying with an arp reply!
· If we change the MAC address of the desktop client for example to (f4:f2:6d:b9:72:dd) and do the arp request again, the WRN802n is replying as expected with an arp reply and the ping works.
· Changing back the MAC address to the original one (00:01:80:7a:bf:d6), clearing the arp cache and doing the arp request again -> NO reply from WRN802n


From our point of view there is maybe a massive bug in the firmware? This failure is a possible show stopper for us…


Who can help?
  0      
  0      
#1
Options

Information

Helpful: 0

Views: 482

Replies: 0

Related Articles