I am stuck in Configuring MT3.24 with proxy arp feature. but nothing achieved. Here I quoted MT ducs to show that even the example does not work. I used this config in the image, but I couldn’t ping host C from host A with Proxy-arp enabled. This is while the same config works on cisco router.Proxy arp is enabled on cisco by default and when I disable it, it would be like MT_this config does not work.
anybody can test the example?
and here is my own topology:http://forum.mikrotik.com/t/routing-public-ips-on-rb493-help/29047/1
Proxy-ARP feature
Description
A router with properly configured proxy ARP feature acts like a transparent ARP proxy between directly connected networks. Consider the following network diagram:
Proxy ARP Diagram
Suppose the host A needs to communicate to host C. To do this, it needs to know host’s C MAC address. As shown on the diagram above, host A has /24 network mask. That makes host A to believe that it is directly connected to the whole 192.168.0.0/24 network. When a computer needs to communicate to another one on a directly connected network, it sends a broadcast ARP request. Therefore host A sends a broadcast ARP request for the host C MAC address.
Broadcast ARP requests are sent to the broadcast MAC address FF:FF:FF:FF:FF:FF. Since the ARP request is a broadcast, it will reach all hosts in the network A, including the router R1, but it will not reach host C, because routers do not forward broadcasts by default. A router with enabled proxy ARP knows that the host C is on another subnet and will reply with its own MAC adress. The router with enabled proxy ARP always answer with its own MAC address if it has a route to the destination.
I upgraded to 3.25…
Proxy-ARP does not reply to ARP requests. when I sniff MAC frames on the interface there comes ARP request in, but no reply is sent out. Proxy-ARP does not work on LAN yet.
I sent it to support team.
I sniffed both interfaces_the interface that client is connected(A or B).It does not make any difference.
these are frames that I can receive on MT. frames don’t have ip address. if I torch, nothing is received.
[admin@MikroTik] > ip route print
Flags: X - disabled, A - active, D - dynamic,
C - connect, S - static, r - rip, b - bgp, o - ospf, m - mme,
B - blackhole, U - unreachable, P - prohibit
# DST-ADDRESS PREF-SRC G GATEWAY DISTANCE INTERFACE
0 ADC 192.168.0.0/25 192.168.0.1 0 ether1
1 ADC 192.168.0.128/25 192.168.0.129 0 ether2
[admin@MikroTik] > /ip address print
Flags: X - disabled, I - invalid, D - dynamic
# ADDRESS NETWORK BROADCAST INTERFACE
0 192.168.0.1/25 192.168.0.0 192.168.0.127 ether1
1 192.168.0.129/25 192.168.0.128 192.168.0.255 ether2
RFC 1027 Definition of Proxy ARP:
“Proxy ARP is the technique in which one host, usually a router, answers ARP requests intended for another machine. By “faking” its identity, the router accepts responsibility for routing packets to the “real” destination. Proxy ARP can help machines on a subnet reach remote subnets without the need to configure routing or a default gateway. Proxy ARP is defined in RFC 1027”
Could you Chupaka give me a working example?
According to RFC1027,cisco and even MT it should work. It may be an OS fault or my fault. I really need it.
I cant get it running on Lan.
Host A doesn’t ping Host C and vice versa…
unfortunately, I don’t have a testing lab to check ARP Proxy, but to be sure… according to the picture in first post (arp-proxy should be running on ether1 of R1), could you please give me the result of ‘tracert’ from C to A, then run ‘ping’ from A to C and simultaneously exec ‘arp -a’ in another command prompt on A. and ‘ipconfig /all’ from both machines. are they all running Windows? =)
