On Thu, April 28, 2016 11:25 am, Gordon Messmer wrote: > On 04/28/2016 02:09 AM, Andreas Benzler wrote: >> ine-imac-andy:~ andy$ ssh -vvvandy at 141.52.135.21 > ... >> debug1: Enabling compatibility mode for protocol 2.0 >> write: Broken pipe >> ine-imac-andy:~ andy$ ssh -vvvandy at 141.52.135.21 > ... >> debug1: SSH2_MSG_SERVICE_REQUEST sent >> ssh_packet_read: Connection reset by peer > > > I see one possibility that explains both the key change and the > connection resets: > > You installed a new server and used an IP address that was already in > use on another server. That's why you already had an SSH key for that > address. The connection resets occur when the client you're using to > connect updates its ARP table and swaps from the MAC address on the new > host to the MAC address on the old host (or visa versa). Oh yes, and bizarre may happen if you have two machines with the same static IP _simultaneously_ on the network. To check if that is the case (for particular IP, say 192.168.2.7) from the machine with different IP on the same subnet 192.168.2.x do arping 192.168.2.7 you will get ARP responses from all machines, and if there is more than one, you will see responces coming from different MAC addresses. Valeri ++++++++++++++++++++++++++++++++++++++++ Valeri Galtsev Sr System Administrator Department of Astronomy and Astrophysics Kavli Institute for Cosmological Physics University of Chicago Phone: 773-702-4247 ++++++++++++++++++++++++++++++++++++++++