Redirect redir errors to /dev/null

[fgrehm]

When no process is listening on the forwarded port on the guest container redir spills up some target: connect: Connection refused errors on the terminal

[dergachev]

@fgrehm,

This change also completely masks errors like redir package not being installed. Instead port forwarding fails, while "vagrant reload" output looks perfect. (Just got bitten by this).

Also if redir isn't able to bind to a port, then it'll print out server: bind: Address already in use which seems useful.

Is there a better way to handle this? At least, is it possible to trap errors from launching redir, currently done using Kernel.spawn?

For future Googlers: At first, I mistook my problem to be the same as the one mentioned in this tutorial:
http://taoofmac.com/space/HOWTO/Vagrant#port-forwarding

For my notes: I was able to reproduce the target: connect: Connection refused message by doing the following:

bash$ screen
screen1$ sudo redir --laddr=127.0.0.1 --lport=9090 --cport=12345 --caddr=10.0.3.226    # nothing listening on 12345
screen2$ curl localhost:9090    # this makes redir spit out 'target: connect: Connection refused' in screen1

[fgrehm]

hey @dergachev, tks for reaching out :)
yeah, I know, vagrant-lxc "user experience" is lacking some love =/ unfortunately I won't have that much of free time until july, so I'll just reopen this issue to keep it on the radar

[fgrehm]

@dergachev (hit submit too early) ... to keep it on the radar, I'll get back to you ASAP

[fgrehm]

@dergachev so I gave this some thought today and I'm leaning towards keeping the redirect if we are not able to think of other issues because:

• we'll detect whether redir is installed or not from Check if dependencies are met #11
• we'll detect if the port is in use and we'll handle collisions from Prevent port colisions #5
• I can't think of another way of preventing target: connect: Connection refused from showing up and there is a huge chance that no process is listening on the forwarded port

what might be a good idea is to allow redirecting stdout and stderr to some log file, like using LXC_START_LOG_FILE for lxc-start stuff.

WDYT?

[asharpe]

I vote for not pushing errors under the rug, especially when there are known cases where we want to see errors. Redirecting to a log file would be soo much better.

[fgrehm]

@dergachev @asharpe checking if redir is installed, forwarded ports collision handling and redir logging has been implemented and will be available from 0.5.0. keep an eye on #122 for more info.