nanog mailing list archives
Re: IP4 address conservation method
From: Bjørn Mork <bjorn () mork no>
Date: Thu, 06 Jun 2013 21:00:12 +0200
William Herrin <bill () herrin us> writes:
On Wed, Jun 5, 2013 at 6:25 PM, Ricky Beam <jfbeam () gmail com> wrote:I won't argue against calling Linux "wrong". However, the linux way of dealing with ARP is well tuned for "host" and not "router" duty.I love Linux and use it throughout my work but I can't tell you the number of times its ARP behavior has bitten me. If you send a packet to a VIP on a Linux box and it doesn't have an arp entry for the default gateway, the Linux box will send an arp request... with the vip as the source. That is just wrong. Wrong, wrong, wrong. Use the damn interface IP when you arp for something on that interface. If the router doesn't happen to like the bad arp (since the VIP isn't on the router's LAN) the router will ignore it. And your service will merrily pop up and down depending on whether the Linux box has any traffic to originate.
Did you try setting sys.net.ipv4.conf.all.arp_announce=2 ? Yes, the system default may be tuned for host/desktop usage, but it's not like you *have* to use the system default. Tweak it as you like. And if there isn't enough knobs, then you can always add another one. You have the source code. Bjørn
Current thread:
- Re: IP4 address conservation method, (continued)
- Re: IP4 address conservation method Dan White (Jun 05)
- Re: IP4 address conservation method Blake Hudson (Jun 06)
- Re: IP4 address conservation method Tore Anderson (Jun 06)
- Re: IP4 address conservation method Blake Hudson (Jun 06)
- Re: IP4 address conservation method William Herrin (Jun 05)
- Re: IP4 address conservation method Mikael Abrahamsson (Jun 05)
- Re: IP4 address conservation method William Herrin (Jun 05)
- Re: IP4 address conservation method Mikael Abrahamsson (Jun 05)
- Re: IP4 address conservation method Dan White (Jun 05)
- Re: IP4 address conservation method Mikael Abrahamsson (Jun 05)
- Re: IP4 address conservation method Dan White (Jun 05)
- Re: IP4 address conservation method Ricky Beam (Jun 05)
- Re: IP4 address conservation method William Herrin (Jun 05)
- Re: IP4 address conservation method Bjørn Mork (Jun 06)
- Re: IP4 address conservation method William Herrin (Jun 06)
- Re: IP4 address conservation method Jimmy Hess (Jun 06)
- Re: IP4 address conservation method William Herrin (Jun 06)
- Re: IP4 address conservation method Bjørn Mork (Jun 07)
- Re: IP4 address conservation method rdrake (Jun 05)
- Re: IP4 address conservation method Jimmy Hess (Jun 05)