Thank you for reaching out.
I understand you have questions regarding private peering for Azure Express Route.
However, from the Azure side, do I only need to add the two /30 subnets? Where are the two private IPs configured?
Yes, you just need to add two /30 subnets. As described here One subnet is used for the primary link, while the other will be used for the secondary link. From each of these subnets, you assign the first usable IP address to your router as Microsoft uses the second usable IP for its router.
But who will configure these two IPs? Should I put them on the Azure side, or do I only need to add the /30 subnets from the Azure portal?
You just need to add two /30 subnets. For each of the /30
subnets, you must use the first IP address of the /30
subnet for your router. Microsoft uses the second IP address of the /30
subnet to set up a BGP session.
If a /29
subnet is used, it's split into two /30
subnets.
You can go through this example here for additional details.
For example
-
192.168.100.128/30
is assigned tolink1
, with provider using192.168.100.129
and Microsoft using192.168.100.130
. -
192.168.100.132/30
is assigned tolink2
, with provider using192.168.100.133
and Microsoft using192.168.100.134
.
Hope this helps. Please let me know if you have any additional questions. Thank you!