On Mon, Apr 29, 2013 at 10:41:24PM +0400, Slawa Olhovchenkov wrote:
If the received route update is exactly the same, then it should be ignored and not propagated further, but there is probably some minor change (like in BGP attributes) that forces the propagation.
How I can see in debug log whats chnged?
There is no easy way, either you could put print commands to import/export filters for specific route attributes (like bgp_path), or you coud try to catch it interactively by 'show route all'.
BIRD currently does not support anything that could prevent propagation of frequent updates.
I thinks this is useful feature.
Yes, but problematic to implement in the current design.
For the kernel protocol it could be hacked by removing the code that handles route updates and depending just on periodic routing table scans for BIRD-kernel routing table synchronization.
This is bad point. For external BGP update this semi-reasonably, but for OSPF/etc this is unacceptable.
Well, for OSPF such problem cannot happen, as OSPF recalculates routes at most once per second. But it is true that it is a hack. -- Elen sila lumenn' omentielvo Ondrej 'SanTiago' Zajicek (email: santiago@crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."