On Sat, 10 Sep 2016 13:15:49 GMT, Chang Long wrote:

simple vibe.d app keep quit, how to fix this?

GNU gdb (Debian 7.7.1+dfsg-5) 7.7.1
Copyright (C) 2014 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later http://gnu.org/licenses/gpl.html
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x8664-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
.
Find the GDB manual and other documentation resources online at:
.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from /root/.ssh/bin/openwrt-dydns-server...done.
Starting program: /root/.ssh/bin/openwrt-dydns-server
[Thread debugging using libthreaddb enabled]
Using host libthreaddb library "/lib/x8664-linux-gnu/libthread_db.so.1".
Listening for requests on http://0.0.0.0:8953/
[New Thread 0x7ffff3e1c700 (LWP 10529)]

Program received signal SIGTERM, Terminated.
0x00007ffff6531e53 in epoll_wait () at ../sysdeps/unix/syscall-template.S:81
81 ../sysdeps/unix/syscall-template.S: No such file or directory.
(gdb) quit
A debugging session is active. 

Inferior 1 [process 10522] will be killed.

Quit anyway? (y or n) [answered Y; input not from terminal]
~

SIGTERM is the usual signal used for requesting a clean shutdown of a process. AFAIK, it is usually only issued by manually running the kill or killall commands. Can it be that something on the system is running and does this explicitly? If it was a SIGKILL instead, the reason could be that the process has used too much memory, but this doesn't seem to be the case here.