add static arp entry to default gateway, arp poison protection

arp -s $(route -n | awk '/^ {print $2}') \ $(arp -n | grep `route -n | awk '/^ {print $2}'`| awk '{print $3}')

By: aramosf
2009-03-25 09:53:10

What Others Think

Careful with this though, especially if it's at a datacenter that are using VRRP. VRRP is *meant* to keep the same MAC address, but some misconfigurations mean it will not.
dotwaffle · 617 weeks and 2 days ago
Handy and interesting but unless you either have a newline after that \ or remove it, you're going to get 'invalid hardware address' back from arp.
TheMightyBuzzard · 617 weeks and 2 days ago
I used postup() in /etc/conf.d/net on my Gentoo box. On OSX, I had to change it a bit: arp -s $(netstat -rn | awk '/^default/ {print $2}') $(arp -an | grep `netstat -rn | awk '/^default/ {print $2}'`| awk '{print $4}')
darkfader · 548 weeks and 4 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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