forked from ebhomengo/niki
60 lines
3.4 KiB
Go
60 lines
3.4 KiB
Go
package opts
|
|
|
|
// defaultHost constant defines the default host string used by docker on Windows
|
|
const defaultHost = "npipe://" + defaultNamedPipe
|
|
|
|
// TODO Windows. Identify bug in GOLang 1.5.1+ and/or Windows Server 2016 TP5.
|
|
// @jhowardmsft, @swernli.
|
|
//
|
|
// 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
|
|
const defaultHTTPHost = "127.0.0.1"
|