IP4 address conservation method

William Herrin bill at herrin.us
Wed Jun 5 16:06:49 UTC 2013


On Tue, Jun 4, 2013 at 6:34 PM, Mikael Abrahamsson <swmike at swm.pp.se> wrote:
> http://www.nanog.org/sites/default/files/tues.general.Papandreou.conservation.24.pdf
>
> So my question is basically: What am I missing?

Both the router and host have to support sending and accepting invalid
ARP requests. Since the Linux kernel already mishandles arp by
default, you're probably begging for unexpected behavior. Double down
on that if the customer controls the server image.

I don't have any experience with softlayer but I have had to abandon a
handful of VPS providers due to bizarre routing failures they couldn't
fix. I was particularly thrilled with the one where if I didn't ping
the second-hop router from each of the VPS's IPs at least once every
15 seconds it would eventually forget how to reach the address. I
could log in via one of the other addresses and confirm with tcpdump
that no arps or anything else would appear on the interface. Their
advice? Disable iptables. Thanks guys, real helpful.

-Bill


-- 
William D. Herrin ................ herrin at dirtside.com  bill at herrin.us
3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
Falls Church, VA 22042-3004




More information about the NANOG mailing list