diff options
Diffstat (limited to 'vendor/github.com/docker/docker/opts/hosts_windows.go')
| -rw-r--r-- | vendor/github.com/docker/docker/opts/hosts_windows.go | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/vendor/github.com/docker/docker/opts/hosts_windows.go b/vendor/github.com/docker/docker/opts/hosts_windows.go new file mode 100644 index 000000000..576236ba4 --- /dev/null +++ b/vendor/github.com/docker/docker/opts/hosts_windows.go @@ -0,0 +1,60 @@ +package opts // import "github.com/docker/docker/opts" + +const ( + // TODO Windows. Identify bug in GOLang 1.5.1+ and/or Windows Server 2016 TP5. + // + // On Windows, this mitigates a problem with the default options of running + // a docker client against a local docker daemon on TP5. + // + // What was found that if the default host is "localhost", even if the client + // (and daemon as this is local) is not physically on a network, and the DNS + // cache is flushed (ipconfig /flushdns), then the client will pause for + // exactly one second when connecting to the daemon for calls. For example + // using docker run windowsservercore cmd, the CLI will send a create followed + // by an attach. You see the delay between the attach finishing and the attach + // being seen by the daemon. + // + // Here's some daemon debug logs with additional debug spew put in. The + // AfterWriteJSON log is the very last thing the daemon does as part of the + // create call. The POST /attach is the second CLI call. Notice the second + // time gap. + // + // time="2015-11-06T13:38:37.259627400-08:00" level=debug msg="After createRootfs" + // time="2015-11-06T13:38:37.263626300-08:00" level=debug msg="After setHostConfig" + // time="2015-11-06T13:38:37.267631200-08:00" level=debug msg="before createContainerPl...." + // time="2015-11-06T13:38:37.271629500-08:00" level=debug msg=ToDiskLocking.... + // time="2015-11-06T13:38:37.275643200-08:00" level=debug msg="loggin event...." + // time="2015-11-06T13:38:37.277627600-08:00" level=debug msg="logged event...." + // time="2015-11-06T13:38:37.279631800-08:00" level=debug msg="In defer func" + // time="2015-11-06T13:38:37.282628100-08:00" level=debug msg="After daemon.create" + // time="2015-11-06T13:38:37.286651700-08:00" level=debug msg="return 2" + // time="2015-11-06T13:38:37.289629500-08:00" level=debug msg="Returned from daemon.ContainerCreate" + // time="2015-11-06T13:38:37.311629100-08:00" level=debug msg="After WriteJSON" + // ... 1 second gap here.... + // time="2015-11-06T13:38:38.317866200-08:00" level=debug msg="Calling POST /v1.22/containers/984758282b842f779e805664b2c95d563adc9a979c8a3973e68c807843ee4757/attach" + // time="2015-11-06T13:38:38.326882500-08:00" level=info msg="POST /v1.22/containers/984758282b842f779e805664b2c95d563adc9a979c8a3973e68c807843ee4757/attach?stderr=1&stdin=1&stdout=1&stream=1" + // + // We suspect this is either a bug introduced in GOLang 1.5.1, or that a change + // in GOLang 1.5.1 (from 1.4.3) is exposing a bug in Windows. In theory, + // the Windows networking stack is supposed to resolve "localhost" internally, + // without hitting DNS, or even reading the hosts file (which is why localhost + // is commented out in the hosts file on Windows). + // + // We have validated that working around this using the actual IPv4 localhost + // address does not cause the delay. + // + // This does not occur with the docker client built with 1.4.3 on the same + // Windows build, regardless of whether the daemon is built using 1.5.1 + // or 1.4.3. It does not occur on Linux. We also verified we see the same thing + // on a cross-compiled Windows binary (from Linux). + // + // Final note: This is a mitigation, not a 'real' fix. It is still susceptible + // to the delay if a user were to do 'docker run -H=tcp://localhost:2375...' + // explicitly. + + // DefaultHTTPHost Default HTTP Host used if only port is provided to -H flag e.g. dockerd -H tcp://:8080 + DefaultHTTPHost = "127.0.0.1" + + // DefaultHost constant defines the default host string used by docker on Windows + DefaultHost = "npipe://" + DefaultNamedPipe +) |