06-02-2008 08:53 AM - edited 03-05-2019 11:21 PM
Hi,
I have the following issue:
Upstream --Fe0/0-- Cisco 7120 --Fe0/1-- Internet Exchange Point
The Cisco router terminates some L2TP tunnels. Each time a tunnel flaps, the router generates the following ARP packet:
Jun 2 18:44:27: IP ARP: sent rep src xxx.xxx.xxx.xxx 0005.5f02.e800,
dst xxx.xxx.xxx.xxx ffff.ffff.ffff FastEthernet0/0
Jun 2 18:44:27: IP ARP: sent rep src xxx.xxx.xxx.xxx 0005.5f02.e801,
dst xxx.xxx.xxx.xxx ffff.ffff.ffff FastEthernet0/1
The ARP packet which is sent via Fe0/1 (to the exchange point) triggers the arpwatch program and the exchange point staff receives an email: New station (xxx.xxx.xxx.xxx) detected.
So is it somehow possible to block this ARP packets on Fe0/1?
The configuration looks like this:
interface Loopback1
ip address yyy.yyy.yyy.yyy 255.255.255.255
no ip redirects
ip route-cache flow
no ip route-cache cef
no ip mroute-cache
!
interface Virtual-Template1
ip unnumbered Loopback1
no ip redirects
no ip proxy-arp
no peer default ip address
ppp mtu adaptive
ppp authentication pap chap ms-chap-v2 callin
!
interface FastEthernet0/0
description Upstream
ip address zzz.zzz.zzz.zzz 255.255.255.248
no ip redirects
no ip proxy-arp
ip route-cache flow
duplex full
speed 100
no cdp enable
!
interface FastEthernet0/1
description Exchange Point
ip address www.www.www.www 255.255.254.0
no ip redirects
no ip proxy-arp
ip route-cache flow
duplex full
speed 100
ipv6 nd suppress-ra
no snmp trap link-status
no cdp enable
no mop enabled
IOS version is: c7100-jk9o3s-mz.122-26a.bin
Thank you!
Solved! Go to Solution.
06-03-2008 12:21 AM
Sounds like gratuitous arp. Try a 'no ip gratuitous-arps' from the config prompt. Let me know how it goes.
06-03-2008 12:21 AM
Sounds like gratuitous arp. Try a 'no ip gratuitous-arps' from the config prompt. Let me know how it goes.
06-03-2008 12:28 AM
*sigh* Didn't think of that, this fixed it.
Thank you alot!
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