wido commented on issue #12210:
URL: https://github.com/apache/cloudstack/issues/12210#issuecomment-3636051898
> You get same/similar result with anycast gateway and EVPN-type2 (MAC+IP)
routes... EVPN provides host routes for each IP, each Hypervisor can have an
anycast gateway for public networks, so the VM's get routed out by their
hypervisors.
>
> This suggestion would, however, require a simpler network setup (EVPN and
VXLAN not needed) and less training and easier to troubleshoot. How does the VM
connect to the outside world or to 169.254.0.1/32, rather? What type of
interface/driver would a VM use?
I have extensive experience with VXLAN+EVPN and I love it, truly do! Many
presentations and talks are about how this works and use it in production.
But, it's complex and you have to deal with an overlay and underlay network.
Equipment which can offload it, handle it. It's not that easy to operate. This
proposal is indeed much simpler and straightforward routing.
If you look at the example I posted above, these are the default routes for
the VM:
```
root@web01:~# ip -6 route show
::1 dev lo proto kernel metric 256 pref medium
2001:678:3a4:100::80 dev ens18 proto kernel metric 256 pref medium
fe80::/64 dev ens18 proto kernel metric 256 pref medium
default via fe80::1 dev ens18 proto static metric 1024 pref medium
root@web01:~# ip -4 route show
default via 169.254.0.1 dev ens18 proto static onlink
root@web01:~#
```
I did a tracepath on this VM (running on Proxmox as a PoC) to Quad9 DNS:
```
root@web01:~# tracepath 9.9.9.9 -n
1?: [LOCALHOST] pmtu 1500
1: 169.254.0.1 0.231ms
1: 169.254.0.1 0.087ms
2: 185.187.12.3 6.733ms
3: 185.187.12.170 0.682ms
4: 193.239.116.123 1.603ms !H
Resume: pmtu 1500
root@web01:~#
```
```
root@web01:~# tracepath 2620:fe::fe -n
1?: [LOCALHOST] 0.018ms pmtu 1500
1: 2001:678:3a4:100::1 0.133ms
1: 2001:678:3a4:100::1 0.096ms
2: 2001:678:3a4:1::2 0.421ms asymm 3
3: 2a0b:8f80::ae 2.988ms asymm 4
4: 2a05:1500:ff00:50::a 0.508ms asymm 3
5: no reply
6: no reply
7: no reply
8: no reply
^C
root@web01:~#
```
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
