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add static arp entry to default gateway, arp poison protection

Terminal - 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}')
2009-03-25 09:53:10
User: aramosf
Functions: arp awk grep route
add static arp entry to default gateway, arp poison protection


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Terminal - Alternatives

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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.

Comment by dotwaffle 431 weeks 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.

Comment by TheMightyBuzzard 430 weeks and 6 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}')
Comment by darkfader 362 weeks and 1 day ago

Your point of view

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