Phoenix Client IP when behind AWS network load balancer

Hey all,

I’m running into an issue when attempting to get the client’s ip address on AWS. My application is running behind a network load balancer, which seems to not set the X-Forwarded-For header. It looks like there is an option to enable Proxy protocol v2 within the target group, but this looks like a binary protocol which needs to be parsed. Has anyone dealt with this before? Has anyone written a decoder for this protocol?


There is some work done by Heroku on Ranch. (Phoenix depends on Cowboy, which depends on Ranch)

This is the result:

It seems like there is however no easy way to integrate this into cowboy / phoenix.

This is the protocol btw:

the classic ELB seems to set x-forwarded-for, according to docs anyway - about to attempt to use it myself.
Have the same issue behind an ELB, that client_ip is that of the load balancer…