Yes, called as you describe, SSH works correctly (it Forwards Agent). Quirky! But, called the way I was doing, everything but Agent Forwarding works. Strange. Looking further, I found another odd behaviour. ssh -o User=vagrant -o Hostname=127.0.0.1 -p 2222 -o Compression=yes -o StrictHostKeyChecking=no -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -o IdentitiesOnly=yes -i /Users/bryanhunt/.vagrant.d/insecure_private_key -o ForwardAgent=yes -o LogLevel=DEBUG "" "/bin/sh -c 'git clone git at bitbucket.org:bryan_picsolve/poc_docker.git /home/vagrant/poc_dockerddd? " Note how I added the empty quoted string in the hostname position. SSH Agent Forwarding works if I add that empty quoted string. If I remove the empty quoted string, the git checkout is executed, but prompts for authentication. I would expect SSH to completely succeed, or completely fail to execute the command - rather than have the side channel (SSH agent) fail or succeed based upon how I express the command line arguments. This is a stock version of the ssh command on OSX. The checksum is: MD5 (/usr/bin/ssh) = 35caacee333ebae93d4087ca349738e4 Perhaps another OSX user could verify this behaviour? Regards, Bryan Hunt On 9 Jan 2014, at 17:21, Markus Friedl <mfriedl at gmail.com> wrote: > You pass it as an option. > > But ssh is called like > > $ ssh [options] hostname [command] > > > > > >> Am 09.01.2014 um 16:21 schrieb bryan hunt <picsolvebryan at gmail.com>: >> >> >> I don?t understand, in the second example, "ssh -o HostName=127.0.0.1 ?, is the very first argument to the program? >> >> >> >>> On 9 Jan 2014, at 13:21, Markus Friedl <mfriedl at gmail.com> wrote: >>> >>> The 2nd example misses the required hostname argument. >>> >>> >>> >>> >>>> Am 09.01.2014 um 13:32 schrieb bryan hunt <picsolvebryan at gmail.com>: >>>> >>>> >>>> Trying to get SSH agent forwarding working for a popular open source configuration management system called Ansible. >>>> >>>> I?ve had some unexpected behaviour, the only cause of which I can find is how I express the command line arguments. >>>> >>>> http://stackoverflow.com/questions/20952689/vagrant-ssh-agent-forwarding-how-is-it-working?noredirect=1#comment31511341_20952689 >>>> >>>> In summarise: >>>> >>>> In the first instance I can create a SSH connection, and and execute a remote git clone (via SSH), the Agent Forwarding works, and I am not prompted for credentials: >>>> >>>> ssh vagrant at 127.0.0.1 -p 2222 \ >>>> -o Compression=yes \ >>>> -o StrictHostKeyChecking=no \ >>>> -o LogLevel=FATAL \ >>>> -o StrictHostKeyChecking=no \ >>>> -o UserKnownHostsFile=/dev/null \ >>>> -o IdentitiesOnly=yes \ >>>> -i /Users/bryanhunt/.vagrant.d/insecure_private_key \ >>>> -o ForwardAgent=yes \ >>>> "/bin/sh -c 'git clone git at bitbucket.org:bryan_picsolve/poc_docker.git /home/vagrant/poc_dockera' " >>>> Cloning into '/home/vagrant/poc_dockera'... >>>> >>>> In the second instance I express the arguments differently ( -o HostName=127.0.0.1 -o User=vagrant ), and Agent Forwarding doesn?t seem to work: >>>> >>>> ssh -o HostName=127.0.0.1 -o User=vagrant -p 2222 \ >>>> -o Compression=yes \ >>>> -o StrictHostKeyChecking=no \ >>>> -o LogLevel=FATAL \ >>>> -o StrictHostKeyChecking=no \ >>>> -o UserKnownHostsFile=/dev/null \ >>>> -o IdentitiesOnly=yes \ >>>> -i /Users/bryanhunt/.vagrant.d/insecure_private_key \ >>>> -o ForwardAgent=yes \ >>>> "/bin/sh -c 'git clone git at bitbucket.org:bryan_picsolve/poc_docker.git /home/vagrant/poc_dockerb' " >>>> /bin/sh -c 'git clone git at 127.0.0.1's password: >>>> >>>> The client side SSH is: >>>> >>>> OpenSSH_6.2p2, OSSLShim 0.9.8r 8 Dec 2011 >>>> >>>> The server side SSH is: >>>> >>>> OpenSSH_5.9p1 Debian-5ubuntu1.1, OpenSSL 1.0.1 14 Mar 2012 >>>> >>>> >>>> Have any of the list members got an insight into this behaviour ? >>>> >>>> Thanks in advance, >>>> >>>> Bryan Hunt >>>> >>>> >>>> >>>> >>>> >>>> >>>> _______________________________________________ >>>> openssh-unix-dev mailing list >>>> openssh-unix-dev at mindrot.org >>>> https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev >>
