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New Member

CPEs same interface connection issues

Actually I have a Cisco 12008 GSR with GE Line Cards, a GE interface is connected to 2960G switch in mode Trunk which receives diferent Base Stations where Customers CPEs are connected. We have created sub-interfaces per every Base Station, the problem faces when two CPEs connected to the same sub-interface (of course on the same ip address range) can not ping each other or communicate using WAN interface, in some Cisco 2821 we solve this issue applying ip local-proxy-arp command on subinterface. Please if somebody knows a similar command on Cisco 12000 GSR or an alternative solution, I really appreciate your help.

Best Regards



Re: CPEs same interface connection issues

Have you gone through the Software Configuration Guide for the Cisco 12000 Series

New Member

Re: CPEs same interface connection issues

Yes, but nothing indicates the reason for this behaviour, the "proxy-arp enable" command must solve that problem but even when its enabled on interfaces doesnt work.


GigabitEthernet4/0.2 is up, line protocol is up

Internet address is

Broadcast address is

Address determined by setup command

MTU is 1500 bytes

Helper address is not set

Directed broadcast forwarding is disabled

Outgoing access list is not set

Inbound access list is not set

Proxy ARP is enabled

Security level is default

Split horizon is enabled

ICMP redirects are always sent

ICMP unreachables are always sent

ICMP mask replies are never sent

IP fast switching is disabled

IP fast switching on the same interface is disabled

IP Flow switching is disabled

IP CEF switching is enabled

IP Null turbo vector

IP multicast fast switching is enabled

IP multicast distributed fast switching is disabled

IP route-cache flags are Fast, Distributed, CEF

Router Discovery is disabled

IP output packet accounting is disabled

IP access violation accounting is disabled

TCP/IP header compression is disabled

RTP/IP header compression is disabled

Probe proxy name replies are disabled

Policy routing is disabled

Network address translation is disabled

WCCP Redirect outbound is disabled

WCCP Redirect inbound is disabled

WCCP Redirect exclude is disabled

BGP Policy Mapping is disabled


Thank you for your help