what is the nodebalancer private ip range?

Hi,

we're using nodebalancers and trusting X-Forwarded-For to determine what is the "real" ip address of our visitors.

So far we have observed that we were hit only by 192.168.255.7 and we have put a rule in our nginx to only trust X-Forwarded-For from this host.

it seems that now, we are queried by other nodebalancer from the 192.168.255.0/24 range. I haven't been able to find some docs indicating what is the "official" range, does somebody have this information?

regards

Vincent