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I have a unique requirement where I need to disable ARP on a Windows 7 box. In previous Windows versions you could modify the ArpRetryCount in the registry (and set it to 0), but this does not work in 7 (nor does it exist).

Does anybody know how, or if this is possible?

I've been asked to elaborate this more and I'm not quite sure how. I want to switch off ARP (including gratuitous arp) on Windows 7 for a project I'm working on. You can do this in Linux by simply adding '-arp' when you bring up an interface, but you cannot do this in Windows 7. You could in previous versions by modifying the registry, but this does not work any more. If the fine folk here aren't sure then I don't like my chances...

DriverGuy
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I know exactly what you're trying to do, it's how I managed to run an active/active web-serving cluster on NetWare. During start up I bound all the cluster IP's to the server with gratuitous arp turned off, Apache loads, disassociate the cluster IP's, start the cluster service. Apache started just fine and stayed up even though it was missing IP binds it started with. That way failovers happened just by moving the active IP between nodes without having to start and stop Apache, much faster and allowed one Apache instance for multiple cluster services. Worked great. I never knew Windows could do that trick (ArpRetryCount, heh).

Looking at the Microsoft documentation (.doc file), Windows 2008 and Windows Vista both still support ArpRetryCount being set in \Tcpip\Parameters. Not per-interface, but globally.

I can't dredge out of the Microsoft KB any information about whether or not this changes for 2008r2/Win7. But the big TCP/IP rewrite happened with Vista/2008 so I'm guessing it still should be supported.

sysadmin1138
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  • Is it possible to disable arp feature completely after setting a static arp entry on Windows? You can do this in Linux. `ip link set dev eth0 arp off` or `ifconfig eth0 -arp`. I don't want my windows device to reply to other device's ARP requests because of some reasons. I will just add the gateway's MAC entry manually. So that my internet connection will work. – Sourav Ghosh Oct 29 '18 at 09:33
  • @SouravGhosh It has been 7 years since I've done much of anything with Windows, and Win8/10/2019 have moved since I last looked in the Win7/2008 era. I honestly don't know anymore. – sysadmin1138 Nov 02 '18 at 15:54