[pve-devel] [PATCH pve-docs 0/1] vxlan l3 routing

[Alexandre DERUMIER]

>>OH, I see. I guess the want/need to avoid multiple bridges on those hardware
>>switches.

yes, indeed, on a hardware switch, you have only 1 bridge (the switch)


>> think it is an interesting lesson, but the setup without vlan is much easier 
>>inside our environment. I guess it is also easier to debug. 

>>Maybe we move those VLAN setup into wiki-artikels, but remove them from 
>>the main docu? 

Sure, no problem. It's indeed more simplier.
we have network reload with ifupdown2, so we can add vxlan/vmbr without reboot easily in config
if we have a lot of bridge/vxlan, we can also use template

%for v in [11,12]:
auto vxlan${v}
iface vxlan${v}
  ....
%endfor



>>My impression is that lwt was there old setup, and they now 
>>move on with frr? 

No, it's different. lwt is not yet supported by ifdown2 (it need a recent kernel 4.13 or 4.15, don't remember)
roopa from cumulus talk about this at netdev 2.2

https://www.netdevconf.org/2.2/slides/prabhu-linuxbridge-tutorial.pdf
https://www.youtube.com/watch?v=OXqJnqH7ZTU&feature=youtu.be

They are trying to reduce the number of interfaces, because on hardware switch, it could take really a long time
to load. (4000 bridge  + 4000 vxlan for example).
That's also why ifupdown2 use netlink directly, to speedup configuration.

That's works fine at layer2, but at layer3, if you need an ip for each vxlan for gateway, you'll need an extra exterface.



----- Mail original -----
De: "dietmar" <dietmar at proxmox.com>
À: "Alexandre Derumier" <aderumier at odiso.com>
Cc: "pve-devel" <pve-devel at pve.proxmox.com>
Envoyé: Samedi 11 Août 2018 09:20:16
Objet: Re: [pve-devel] [PATCH pve-docs 0/1] vxlan l3 routing

> >>BTW, the existing vxlan-and-evpn.adoc explain howto setup vxlan on vlan. 
> >>I can see that this works, but why would someone do that? 
> 
> Maybe because it's reduce the configuration, don't need to create 1bridge for 
> 1vxlan. 

OH, I see. I guess the want/need to avoid multiple bridges on those hardware 
switches. 

> I have added the doc if they want it, but we could remove it if you want, to 
> have less differents setup and remove complexity for users. 

I think it is an interesting lesson, but the setup without vlan is much easier 
inside our environment. I guess it is also easier to debug. 

Maybe we move those VLAN setup into wiki-artikels, but remove them from 
the main docu? 

> I known that cumulus is working on lwt vxlan (lightway tunnel), 
> where you can have 1 vxlan interface - 1 vlan aware bridge, and vlan are 
> mapped to vxlan when going out. 
> But that don't work with frr currently, and with l3 routing, anyway, you need 
> to define interface with gateway ip on each vlan. 

My impression is that lwt was there old setup, and they now 
move on with frr?