I can tell which path my traffic takes from my location to a remote site (e.g. whatever.1e100.net) by using traceroute. But I would like to verify what path traffic from whatever.1e100.net takes on its way back to my site. Without having a bud at the remote site to perform this for me ... how might I do this?
It seems to me that I can identify the Autonomous System number associated with this route through a number of mechanisms ... turns out to be '15169'
How do I go about finding a Looking Glass server (from which I could launch a traceroute back toward me) living inside AS 15169?
Poking around, I found www.peeringdb.net ... regrettably, this database does not report a Looking Glass URL for AS 15169 ... perhaps I have hit a dead-end
We are not sure whether 15169 is actually the remote AS number or is an effort to disguise the AS number of the remote site. So it is difficult to give good advice. And we do not know whether this AS is a private enterprise (less likely to have a publicly accessible Looking Glass) or is a provider (more likely to have a publicly accessible Looking Glass). And we do not know whether you do have some relationship with the AS or not. Can you provide some clarification?
The information I provided in my original post is accurate, minus the hostname 'whatever'.
i.e. in this particular example, I am wanting to traceroute from AS 15169, as the hosts which interest me live inside 126.96.36.199/24, which is a Google space (search for 'what is 1e100.net') for more detail
More generically though, does the work-flow for tackling this kind of problem look as follows?
! Find the AS number associated with the host
==> AS 12345
! Search for a Looking Glass server associated with this AS
Try searching this Web page: https://bgp4.as/looking-glasses
! If you find a hit, then run traceroute from the resulting Looking Glass server
! If you have missed, then you are stuck