docker-machine ls: Timeout error when instance has been stopped

[janeczku]

$ docker-machine ls

NAME              ACTIVE   DRIVER       STATE     URL                        SWARM   DOCKER    ERRORS
node01            -        openstack    Running   tcp://92.XXX.XXX.204:2376           v1.9.1

$ docker-machine stop node01

Stopping "node01"...
Machine "node01" was stopped.

$ docker-machine ls

NAME              ACTIVE   DRIVER       STATE     URL                        SWARM   DOCKER    ERRORS
node01            -        openstack    Timeout  

This is obviously doomed to fail, with commit 670c480 assuming incorrectly that when the driver returns the URL it means that the machine is running.

https://github.com/docker/machine/blob/master/commands/ls.go#L343-L347

/cc @dgageot

Version Info:
docker-machine version 0.6.0, build e27fb87

[dgageot]

@janeczku The (implicit?) contract with GetUrl() is that it should return the url only if the machine is running. I'll take a look at fixing GetUrl() in the openstack driver.

[janeczku]

Hi @dgageot, are you sure? I haven't seen any driver that behaves the way you described it. They all construct the URL from the IP address, so the only implicit requirement to return an URL is that the machine has an IP address. E.g.: https://github.com/docker/machine/blob/master/drivers/digitalocean/digitalocean.go#L257-L258

[dgageot]

@janeczku Yes, I'm sure ;-) GetIP often checks for the VM state or implicitly fails if the VM is not running since it gets an IP only if it's running

[janeczku]

I beg to differ:
https://github.com/docker/machine/blob/master/libmachine/drivers/base.go#L38-L44

Nothing being checked here. It just returns the IP from the JSON store.

[dgageot]

@janeczku Let me be clearer: every driver that relies on the default implementation of GetIP and/or returns an IP without checking that the VM is running is flawed. If it needs to be fixed then it needs to fixed. All local VM drivers behave OK. Some cloud drivers are OK. Some are not OK.

[janeczku]

Let me be clearer: every driver that relies on the default implementation of GetIP and/or returns an IP without checking that the VM is running is flawed.

Thanks. Now we are talking 😄

[janeczku]

Here is the list of drivers that according to @dgageot are flawed in that they return the machine IP and/or URL without checking that the machine is actually running (Hint: All the the cloud drivers):

https://github.com/docker/machine/blob/master/drivers/vmwarevcloudair/vcloudair.go
https://github.com/docker/machine/blob/master/drivers/azure/azure.go
https://github.com/docker/machine/blob/master/drivers/amazonec2/amazonec2.go
https://github.com/docker/machine/blob/master/drivers/digitalocean/digitalocean.go
https://github.com/docker/machine/blob/master/drivers/exoscale/exoscale.go
https://github.com/docker/machine/blob/master/drivers/google/google.go
https://github.com/docker/machine/blob/master/drivers/hyperv/hyperv.go
https://github.com/docker/machine/blob/master/drivers/openstack/openstack.go
https://github.com/docker/machine/blob/master/drivers/rackspace/rackspace.go
https://github.com/docker/machine/blob/master/drivers/softlayer/driver.go

Stopped machines using these drivers will cause docker-machine ls to take around 10 seconds to complete and display a timeout error.

[dgageot]

@janeczku Thanks for the inventory. I worked on it yesterday and will create a PR soon. Some of the drivers you listed are not flawed. Here's the list of drivers that have to be fixed:

https://github.com/docker/machine/blob/master/drivers/amazonec2/amazonec2.go
https://github.com/docker/machine/blob/master/drivers/azure/azure.go
https://github.com/docker/machine/blob/master/drivers/digitalocean/digitalocean.go
https://github.com/docker/machine/blob/master/drivers/exoscale/exoscale.go
https://github.com/docker/machine/blob/master/drivers/openstack/openstack.go
https://github.com/docker/machine/blob/master/drivers/softlayer/driver.go
https://github.com/docker/machine/blob/master/drivers/vmwarevcloudair/vcloudair.go

[dgageot]

Related to #1296

[janeczku]

👍 Great