I'm not saying I *would* do it, or you *should* do it, I'm just answering the questions being asked. :) On Thu, Jan 2, 2025 at 3:21 PM Christopher Morrow <morrowc.lists@gmail.com> wrote:
On Thu, Jan 2, 2025 at 2:55 PM Tom Beecher <beecher@beecher.cc> wrote:
Jean-
Thanks. Many BGP implementations have the ability to do conditional
advertisements, where you announce (or don't) a set of prefixes based on the presents (or absence) of other routes. I don't think quagga does natively, and not sure if VyOS has added that on.
Conceptually, you want to be doing "announce these prefixes from this
router only if I don't see routes from the upstream on the other router". The 'safest' way is probably to just monitor default, but it depends on your environment.
That sort of thing seems like extra complexity, no? If the 2 internal routers have iBGP and you are fairly sure that you won't lose that path/view you should be able to just announce the same prefixes to both ISP peerings and possibly add some metric-equivalent data to distance one link vs the other, no? (common metric for this is the as-path, add your as N times, where N is <10 and > 2 probably?)
how exact do you want your split here to be jfranco ? (is 'mostly everything over PRIMARY with some over SECONDARY' ok?)
On Fri, Dec 27, 2024 at 6:09 PM Jean Franco <jfranco@maila.inf.br> wrote:
Hi Tom, This is exactly what I was planning. I'm announcing a block via ISP1 and another set of blocks via ISP2, and
have iBGP running between them.
Thanks a lot!!
Best regards,
On Fri, Dec 27, 2024 at 1:00 PM Tom Beecher <beecher@beecher.cc> wrote:
Jean-
Yeah, don't worry about people complaining.
Is this an accurate description of what you are trying to achieve?
- Have 2 different sets of prefixes that you announce. Set A via
- If BGP to one of your ISPs goes down, start announcing those
router1/ISP1 , Set B via router2/ISP2 prefixes to the other ISP. ( Example, if ISP2 goes down, start announcing prefix Set B over ISP1 )
On Thu, Dec 26, 2024 at 8:16 AM Jean Franco <jfranco@maila.inf.br>
wrote:
Hi guys, I've been on the list for as long as I cannot even remember. So just you know, I'm not new at this.
This is no easy task, that's why I came here looking for help. I'm sorry if I brought anguish to the experts on the list! I thought I could bring something that someone may have experienced
before.
I haven't solved this yet, but at least I've received some valuable
suggestions and I Thank you!
About all the details of the connections, numbers of peerings, PNI's
and IXP's I have left them out, since I figured this additional information could make things worse.
ISP 1 <router01> ====20KM====<Router>====20KM====<router02> ISP2
The ISP connections are all 10G. I don't believe these routers are DFZ capable. All the routers are well capable and already receive the full routes. The connections between these routers are 40G.
Best regards,
On Thu, Dec 26, 2024 at 12:53 AM Bryan Fields <Bryan@bryanfields.net>
wrote:
On 12/25/24 6:18 PM, Randy Bush wrote: > where does one go for is-is help? the mtu issie can be painful!!!
I think here would be good too. I recently had to do this between a
Cisco
3945e and a Juniper, and from my unrevised notes:
vlan { unit 405 { family iso { # holy shit this is important. CISCO and Juniper will not talk unless the MTU is set mtu 1492; } } }
:-)
-- Bryan Fields
727-409-1194 - Voice http://bryanfields.net