Yes the issue is only with case 3) Actually I found this issue when I wanted to run a measurement using non-RFC1918 probes only. I found my SW probes are all marked with System-tag IPv4 RFC1918 although there is public IPv4 present. See my probe 1000069 is tagged with System-tag IPv4 RFC1918 even there is public IPv4, and measurements do correctly state "src_addr":"95.85.x.x" Probe Address Discovery IPv4 IPv6 Connection Address - 2a01:510:xxxx:4888::1 IP Echo Service 95.85.x.x 2a01:510:xxxx:4888::1 The Local IP 192.168.1.1 2a01:510:xxxx:48ff::1 For IPv6 it is different story. On the web page all the IPv6 are listed correctly, but measurements show "src_addr":"2a01:510:xxxx:4888::1" as well as the "Connection Address" does. While the Default Route it different interface with something like 2a01:510:d5:xxxx:xxxx:xxxx:xxxx:xxxx address. Conclusion: - how can I have my probe 1000069 not tagged IPv4 RFC1918? - how can I make the probe use the default outgoing interface mentioned above? Cheers Jiri ______________________________________________________________
Od: "Philip Homburg" <philip.homburg@ripe.net> Komu: atlas-sw-probes@ripe.net Datum: 25.05.2020 10:43 Předmět: Re: [atlas-sw-probes] How to force the SW Probe to use particular IP Interface / IP Address?
On 2020/05/24 9:36 , ripe@brite.cz wrote:
is there a way how to force the SW Probe to use particular IP Interface / IP Address?
1. Turris Omnia Router: 1a - there is public IPv4 on WAN interface, but the probe choose LAN interface that is behind NAT, what is not necessary and would be better to choose the WAN. 1b - I have multiple IPv6 interfaces, the probe keeps choosing the one I use for testing and therefore is not as stable as the others. I would like the probe to use WAN6 interface instead.
2. CentOS virtual machine - there is public IPv4 and local IPv4 RFC1918, again, the probe choose the local instead of the public IP. It's a pity, the probe better use the public one.
For probes we basically have 3 types of addresses: 1) Addresses used for measurements. Those show up in measurement results as 'src_addr'. These are determined by the linux kernel on how best to route the outgoing packet. As long as the probe has one default route, that typically works. 2) The public address of the probe. This is taken from connections to our infrastructure. 3) The local address of the probe as reported on the website. Note that this address is not really used for anything except to show it on the website. Here we can do better. Because we just take the first address we find, instead of taking an address for an interface with a default route.
Note, if you see something wrong case 1) and 2) then we have to investigate. Case 3) is on our list to look into.
Philip