Subject: Re: [44net] Tunnel mesh is (mostly) down From: "John Wiseman" john.wiseman@cantab.net Date: 01/04/2015 10:09 AM
To: "'AMPRNet working group'" 44net@hamradio.ucsd.edu
Wouldn't the simplest solution be to modify the rip44 process so it doesn't delete routes that haven't been announced for a while, or at least for a much longer period?
IPIP tunnels and RIP have the major advantage that they allow those who have a dynamic IP address to participate in net44. I feel it is important that we remember that we are radio hams first, and should use solutions that can be used by the majority of hams, not just those network professionals who want to play a being an ISP.
73, John G8BPQ
That sounds like a good idea, John. The ampr-ripd has a route lifetime of only 600 seconds. Routes are announced every 300 seconds, so when two subsequent announces are incomplete we lose the route. It happened again this morning at 08:05 local (07:05 UTC). My route again was lost, and recovered at 08:10.
I think I'll recompile ampr-ripd with a bit larger timeout. Marius, what do you think? Does this have any negative consequences? (e.g. to change EXPTIME from 600 to 3600 or even 7200)
However, aside from that, the source of the problem should be located, or it will bite us again in the future. There could be big packet loss on the link from UCSD, or maybe some buffer overflow internal to the RIP server (I think it sends big bursts of data rather than slowly throttled streams), or it could be the RIP server somehow sends shortened information because it temporarily does not have the full route list, e.g. because the portal sends an incomplete list.
This has to be investigated or else it will come back. I predict. (I mention this because I recently had a long discussion with someone who thinks that we can live with malfunctioning solutions because we are amateurs. I think we should strive for correctly working systems anyway. And that a system that works well in practice is always better than a system that works well in theory but does not work in real life)
Rob