mesos git commit: Slave exits gracefully on DNS lookup failure.

[be...@apache.org]

Repository: mesos
Updated Branches:
  refs/heads/master bfa89f22e -> d43b9df4a


Slave exits gracefully on DNS lookup failure.

Jira: MESOS-2962

Slave fails with Abort stacktrace when DNS cannot resolve hostname.

If the DNS cannot resolve the hostname for a slave node, we correctly
return an Error object, but we then fail with a segfault.

This code adds a more user-friendly message and exits normally (with
an `EXIT_FAILURE` code).

For example, forcing `net::getIp()` to always return an Error, now
causes the slave to exit like this:

```
$ ./bin/mesos-slave.sh --master=10.10.1.121:5405
Failed to obtain the IP address for 'stratos.local'; the DNS service may not be able to resolve it: Name or service not known

$ echo $?
1
```

Review: https://reviews.apache.org/r/36061


Project: http://git-wip-us.apache.org/repos/asf/mesos/repo
Commit: http://git-wip-us.apache.org/repos/asf/mesos/commit/d43b9df4
Tree: http://git-wip-us.apache.org/repos/asf/mesos/tree/d43b9df4
Diff: http://git-wip-us.apache.org/repos/asf/mesos/diff/d43b9df4

Branch: refs/heads/master
Commit: d43b9df4a1cb3a315c33f3244b631faf5004a301
Parents: bfa89f2
Author: Marco Massenzio <ma...@mesosphere.io>
Authored: Wed Jul 1 17:12:53 2015 -0700
Committer: Benjamin Hindman <be...@gmail.com>
Committed: Wed Jul 1 17:12:54 2015 -0700

----------------------------------------------------------------------
 3rdparty/libprocess/src/process.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/mesos/blob/d43b9df4/3rdparty/libprocess/src/process.cpp
----------------------------------------------------------------------
diff --git a/3rdparty/libprocess/src/process.cpp b/3rdparty/libprocess/src/process.cpp
index b754fb3..2d29d96 100644
--- a/3rdparty/libprocess/src/process.cpp
+++ b/3rdparty/libprocess/src/process.cpp
@@ -896,7 +896,9 @@ void initialize(const string& delegate)
     Try<net::IP> ip = net::getIP(hostname, __address__.ip.family());
 
     if (ip.isError()) {
-      LOG(FATAL) << ip.error();
+      EXIT(EXIT_FAILURE) << "Failed to obtain the IP address for '" << hostname
+                         << "'; the DNS service may not be able to resolve it: "
+                         << ip.error();
     }
 
     __address__.ip = ip.get();