Global Akamai Outage

Mon Jul 26 17:04:41 UTC 2021

Hello!

On Mon, 26 Jul 2021 at 17:50, heasley <heas at shrubbery.net> wrote:
>
> Mon, Jul 26, 2021 at 02:20:39PM +0200, Lukas Tribus:
> > rpki-client 7.1 emits a new per VRP attribute: expires, which makes it
> > possible for RTR servers to stop considering outdated VRP's:
> > https://github.com/rpki-client/rpki-client-openbsd/commit/9e48b3b6ad416f40ac3b5b265351ae0bb13ca925
>
> Since rpki-client removes "outdated" (expired) VRPs, how does an RTR
> server "stop considering" something that does not exist from its PoV?

rpki-client can only remove outdated VRP's, if it a) actually runs and
b) if it successfully completes a validation cycle. It also needs to
do this BEFORE the RTR server distributes data.

If rpki-client for whatever reason doesn't complete a validation cycle
[doesn't start, crashes, cannot write to the file] it will not be able
to update the file, which stayrtr reads and distributes.

If your VM went down with both rpki-client and stayrtr, and it stays
down for 2 days (maybe a nasty storage or virtualization problem or
maybe this just a PSU failure in a SPOF server), when the VM comes
backup, stayrtr will read and distribute 2 days old data - after all -
rpki-client is a periodic cronjob while stayrtr will start
immediately, so there will be plenty of time to distribute obsolete
VRP's. Just because you have another validator and RTR server in
another region that was always available, doesn't mean that the
erroneous and obsolete data served by this server will be ignored.

There are more reasons and failure scenarios why this 2 piece setup
(periodic RPKI validation, separate RTR daemon) can become a "split
brain". As you implement more complicated setups (a single global RPKI
validation result is distributed to regional RTR servers - the
cloudflare approach), things get even more complicated. Generally I
prefer the all in one approach for these reasons (FORT validator).

At least if it crashes, it takes down the RTR server with it:

https://github.com/NICMx/FORT-validator/issues/40#issuecomment-695054163

But I have to emphasize that all those are just examples. Unknown bugs
or corner cases can lead to similar behavior in "all in one" daemons
like Fort and Routinator. That's why specific improvements absolutely
do not mean we don't have to monitor the RTR servers.

lukas