Posts Tagged ssh-agent
Because I am feeling accomplished, and because I also want to avoid my physics homework.
I think I’ve got a pretty good system working for CS137 (and the UW CS servers) now. I’ve got:
- sshag working, so I don’t have to eval `ssh-agent` && ssh-add each time I open a new screen session
- a modified version of the marmoset_sumbit script that now automatically adds a tag in git with the assignment & submission number when I submit an assignment through the command line
- bash actually working and running .bashrc when I login, instead of having to manually run it each time
I’ve known about ssh-agent for a while, but as I was practically permanently using PuTTY (on Windows), I only bothered with learning about Pageant.
But Git uses ssh to connect to github, and I was getting tired of typing in my password with every push. I got annoyed with InteliJ for making me type in my password in with every push, and this was no different. Because git uses bash as its’ command line on both Windows and Linux, I decided to get started with using ssh-agent.
The first time I ran ssh-agent expecting it to work automagically. Instead it dumped what looked like two environment variables to the screen and quit. Not too helpful, but I manually copied, formatted & pasted the variables, and got it working.
But doing that manually, while awesome when pushing from one system and pulling on another, was also annoying with having to do it every time I logged in. So I looked into automating it. I knew of eval and backticks in bash. So I tried `ssh-agent`.
sh.exe": SSH_AUTH_SOCK=/tmp/ssh-myYvgp1404/agent.1404;: No such file or directory
Hmm. No joy. Ok, let’s try eval ssh-agent. Maybe that’ll make a difference?
$ eval ssh-agent
SSH_AUTH_SOCK=/tmp/ssh-zIQZKN6080/agent.6080; export SSH_AUTH_SOCK;
SSH_AGENT_PID=1092; export SSH_AGENT_PID;
echo Agent pid 1092;
Nope, back to manually editing it. Hmm. Google search time.
Which led me to a uni helpdesk page. Which told me that I had to use both eval and backticks. Huh. How ingenious.
$ eval `ssh-agent`
Agent pid 4288
OH HEY THAT LOOKS GOOD.
So I gleefully ran it on the uni’s servers. And then discovered I had to run it in every bash shell. Hmm. Sounds kind of unoptimal. Fixed my original problem, which was having to type in my password each and every time I pushed or pulled from github. And using eval and backticks meant it was easier than copy & pasting the output. But I didn’t like having to run ssh-add and ssh-agent in every new session, or that ssh-agent wouldn’t auto-terminate when I closed bash. (Which led to a surprise when I ran
ps u and saw at least 8 ssh-agent processes running with my username.)
So I just ran it in a screen session. And just have to use that one window everytime. Fairly straightforward.
The alternative was add to the commands to my .bashrc. But the uni servers seem to do something to bash such that it doesn’t execute a user’s bashrc when they login, only after they run bash. So running it in screen works just as well, since I’d need to run a command anyway.
As an alternative alternative, I also found a script that should work for keeping track of ssh-agent and can be run from .bashrc, so I’ll be looking into that too.