Re: address pair exploration, flooding and state loss

[Erik Nordmark <erik.nordmark@sun.com>]

Iljitsch van Beijnum wrote:
> On 27-mei-2005, at 22:57, Erik Nordmark wrote:
>
> > 2. The box reboots in 30 seconds. TCP retransmissions for the next  10 
> > minutes are silently dropped because the retransmissions arrive  at 
> > the peer's TCP with a bad checksum (due to "missing" shim6  rewrite).
> > Thus any RST doesn't arrive until 10 minutes or so later!
>
>
> Can we create a new ICMP message that says "I got a packet that may  or 
> may not have come from you and it had a wrong layer 4 checksum"?

And modify every transport protocol implementation? I'd prefer if we 
don't have to rely on such modifications.

> On a slightly related note: it would be good if we can rebuild shim  
> state after it has been lost on one side when at the same time, there  
> is a failure. This would allow new sessions to be created and  
> immediately rehomed that would otherwise have failed.

Presumably when A discovers that B has lost the shim state and it had 
failed over to an alternate locator pair, it will immediately try to 
rebuilt it, before sending any more ULP packets.
In this case it makes sense for A to use the locator pair that was 
working before the state loss for the shim6 signaling (and if possible, 
tell B which locator pair was used in the reverse direction).

I don't know how important it would be to optimize this case though.

  Erik