Perhaps my expectations or syntax is incorrect, but I see what looks
like difficulty reading stdin using ssh-keyscan:
$ ssh-keyscan -t rsa login.itd.umich.edu | ssh-keygen -l -f -
-: No such file or directory
Instead of the error message "-: No such file or directory", I would
expect the output from ssh-keyscan to be read into ssh-keygen in the
above example and the fingerprint produced as output.
Doing it in two steps works:
$ ssh-keyscan -t rsa login.itd.umich.edu >/tmp/x;ssh-keygen -l -f /tmp/x
# login.itd.umich.edu SSH-1.99-OpenSSH_4.6p1-hpn12v17
1024 10:4a:ec:d2:f1:38:f7:ea:0a:a0:0f:17:57:ea:a6:16 login.itd.umich.edu
Option -f filename, Filename of the key file, seems to be the right
option and '-' is the usual way of indicating stdin.
regards,
-Lars