I've had som emore experience with this, and it is definitely true that running ssh-keyscan host1 host2 host3 host4 ....
can end up giving output only for a small number of hosts because a single host fails. During one case where this was failing, i did (manually) $ ssh-keyscan -t rsa,dsa ec2-67-202-18-160.compute-1.amazonaws.com ec2-184-72-94-230.compute-1.amazonaws.com ec2-75-101-179-107.compute-1.amazonaws.com ... # ec2-67-202-18-160.compute-1.amazonaws.com SSH-2.0-OpenSSH_5.8p1 Debian-1ubuntu1 ec2-67-202-18-160.compute-1.amazonaws.com ssh-dss AAAAB3N... # ec2-67-202-18-160.compute-1.amazonaws.com SSH-2.0-OpenSSH_5.8p1 Debian-1ubuntu1 ec2-67-202-18-160.compute-1.amazonaws.com ssh-rsa AAAAB3NzaC1y... # ec2-184-72-94-230.compute-1.amazonaws.com SSH-2.0-OpenSSH_5.8p1 Debian-1ubuntu1 Connection closed by 184.72.94.230 There were several other hosts to scan (13), but the failure of 'Connection closed' on the third host ends up failing. I had assumed from the man page of ssh-keyscan: "ssh-keyscan uses non-blocking socket I/O to contact as many hosts as possible in parallel, so it is very efficient. The keys from a domain of 1,000 hosts can be collected in tens of seconds, even when some of those hosts are down or do not run ssh." that a failure on one host would not indicate the others, but it appears that is not the case. So, in the case where I saw large number of ssh-keyscan failures, they are in fact linked to 2 failure. -- You received this bug notification because you are a member of Ubuntu Server Team, which is subscribed to cloud-init in ubuntu. https://bugs.launchpad.net/bugs/656646 Title: transient network/keyscan issues -- Ubuntu-server-bugs mailing list Ubuntu-server-bugs@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-server-bugs
