посмотри кто там в слейвах, кого он ждёт, и его стрейс
ждет он ruby, вот часть strace -f ...
...
[pid 860] close(7) = 0
[pid 860] lstat("/tmp/vagrant-bundle-app-config20160918-860-eqiqg4/config", {st_mode=S_IFREG|0644, st_size=41, ...}) = 0
[pid 860] unlink("/tmp/vagrant-bundle-app-config20160918-860-eqiqg4/config") = 0
[pid 860] rmdir("/tmp/vagrant-bundle-app-config20160918-860-eqiqg4") = 0
[pid 860] unlink("/tmp/vagrant-configfile20160918-860-147l0ex") = 0
[pid 860] unlink("/tmp/vagrant-gemfile20160918-860-8gfwn5") = 0
[pid 860] unlink("/tmp/vagrant-gemfile20160918-860-8gfwn5.lock") = 0
[pid 860] write(4, "!", 1 <unfinished ...>
[pid 862] <... poll resumed> ) = 1 ([{fd=3, revents=POLLIN}])
[pid 860] <... write resumed> ) = 1
[pid 862] read(3, <unfinished ...>
[pid 860] tgkill(860, 863, SIGVTALRM <unfinished ...>
[pid 862] <... read resumed> "!", 1024) = 1
[pid 860] <... tgkill resumed> ) = 0
[pid 863] <... read resumed> 0x7f24a5483a96, 2) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
[pid 862] read(3, <unfinished ...>
[pid 863] --- SIGVTALRM {si_signo=SIGVTALRM, si_code=SI_TKILL, si_pid=860, si_uid=1000} ---
[pid 862] <... read resumed> 0x7f24aa247fa0, 1024) = -1 EAGAIN (Resource temporarily unavailable)
[pid 863] rt_sigreturn({mask=[]} <unfinished ...>
[pid 862] read(5, <unfinished ...>
[pid 863] <... rt_sigreturn resumed> ) = -1 EINTR (Interrupted system call)
[pid 862] <... read resumed> 0x7f24aa247fa0, 1024) = -1 EAGAIN (Resource temporarily unavailable)
[pid 863] read(11, <unfinished ...>
[pid 862] tgkill(860, 863, SIGVTALRM <unfinished ...>
[pid 860] futex(0x1d156a4, FUTEX_WAIT_PRIVATE, 3, NULL <unfinished ...>
[pid 863] <... read resumed> 0x7f24a5483a96, 2) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
[pid 862] <... tgkill resumed> ) = 0
[pid 863] --- SIGVTALRM {si_signo=SIGVTALRM, si_code=SI_TKILL, si_pid=860, si_uid=1000} ---
[pid 862] poll([{fd=3, events=POLLIN}], 1, 100 <unfinished ...>
[pid 863] rt_sigreturn({mask=[]}) = -1 EINTR (Interrupted system call)
[pid 863] read(11, <unfinished ...>
[pid 862] <... poll resumed> ) = 0 (Timeout)
[pid 862] tgkill(860, 863, SIGVTALRM) = 0
[pid 863] <... read resumed> 0x7f24a5483a96, 2) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
[pid 862] poll([{fd=3, events=POLLIN}], 1, 100 <unfinished ...>
[pid 863] --- SIGVTALRM {si_signo=SIGVTALRM, si_code=SI_TKILL, si_pid=860, si_uid=1000} ---
[pid 863] rt_sigreturn({mask=[]}) = -1 EINTR (Interrupted system call)
[pid 863] read(11, <unfinished ...>
... дальше все циклится read(11, ...)