Am 18.05.2015 um 18:25 schrieb Gordon Messmer <gordon.messmer at gmail.com>: > On 05/16/2015 10:23 AM, Leon Fauster wrote: >> Well, the destination is not in my realm (different provider). Before >> contacting them I want to be sure that my system is not causing this. >> So far i just see a "tcp retransmission" while trying to establish >> a https connection (captured on our router): > > That can be difficult to establish. If you're getting no response, the most likely problems > are either a bad route or a firewall rule somewhere along the path. The problem could exist > at anywhere along the path, and they'll typically both look the same according to tests at your host. > > As Anthony pointed out, you can use hping3 in TCP traceroute mode to determine where along > the path the problem probably exists. The first host to not respond should be the host with > the problem. Hopefully you have access to a host that has access and a similar path to the > host you can't reach. If so, the same hping3 command should give you the complete traceroute > path, and from there you can find the host that didn't respond in the first test. I could determine that the problem didn't sits on our systems now. The carrier of the endpoint has a ticket open now and I'm betting with my colleagues how fast they will be :-) Thanks for the pointers! -- LF