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TechT's avatar
TechT
Icon for Nimbostratus rankNimbostratus
Jan 09, 2017

Proxy arp disable

Hi,

 

I have a Forwarding VIP which is configured for /24 subnet with ARP and ICMP echo enabled, i see all the hosts are reachable from the subnet if the hosts are alive (or) NOT alive. I guess this is something expected behaviour of LTM where the connections are proxying and returning to ping. Could anyone let me know how can i disable the proxy arp for the hosts which are not live in the network. (iRule or inbuilt option is also fine)

 

application delivery
iRules
LTM
  • Kai_Wilke's avatar
    Kai_Wilke
    Icon for MVP rankMVP
    Jan 10, 2017

    Hi Maneesh,

    to transparently forward ICMP-PING packets to the destination IPs, you have to turn off "ICMP Echo" and "ARP" on the 10.X.33.0 Virtual Address object.

    ltm virtual-address 10.X.33.0 {
    address 10.X.33.0
    arp disabled
    icmp-echo disabled
    mask 255.255.255.0
    spanning enabled
    traffic-group traffic-group-1
}

    After the change your F5 should stop to answer ICMP-Pings for IPs that are either not in use nor currently reachable.

    Cheers, Kai