On 2/15/12 10:56 , Daniel Roesen wrote: > On Wed, Feb 15, 2012 at 12:24:50PM -0500, Stefan Fouant wrote: >> The cool thing is the Backup RE is actually listening to all the >> control plane messages coming on fxp1 destined for the Master RE >> and formulating it's own decisions, running its own Dijkstra, >> BGP Path Selection, etc. This is a preferred approach as opposed >> to simply mirroring routing state from the Primary to the Backup >> is because it eliminates fate sharing where there may be a bug >> on the Primary RE, we don't want to create a carbon copy of that >> on the Backup. > > I don't really buy that argument. Running the same code with the same > algorithm against the same data usually leads to the same results. > You'll get full bug redundancy - I'd expect RE crashing simultaneously. > Did NSR protect from any of the recent BGP bugs? > > The advantage I see are less impacting failovers in case of a) hardware > failures of active RE, or b) data structure corruption happening on both > REs [same code => same bugs], but eventually leading to a crash of the > active RE sooner than on the backup RE, or c) race conditions being > triggered sufficiently differently timing-wise so only active RE > crashes.
when ISSU actually works it's a godsend. > Am I missing something? > > Best regards, > Daniel > _______________________________________________ juniper-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/juniper-nsp
