Hi, I have two probes that seem to work just fine; their built-in measurements work, I can see their results from my "My Atlas" page, etc. I happened to notice something weird about the ping times to c.root-servers.net, so wanted to define a traceroute measurement to see if there were route changes that could explain what I saw. However, the only result that I'm getting is "error": "name resolution failed: non-recoverable failure in name resolution". I picked "Resolve on probe", and used "c.root-servers.net" as the destination. I'm pretty sure I didn't make a typo, because I've copy-n-pasted from the dst_name of the result JSON. For reference, the UDM ID is 1010361 and the probes are 4936 and 4938. Each probe has a working DNS server configured, according to the "My Probes" view. Thanks for any help, Bill (P.S. I created a new UDM using the IP address, to work around the DNS problem, but it'd still be nice to understand what I did wrong with the other one.)