Unable to export container

[maltyyev]

Expected behavior

Export container to mysql.tar

Actual behavior

Error response from daemon: Bad response from Docker engine

Information

Docker for Mac: version: 17.12.0-ce-mac55 (18467c0ae7afb7a736e304f991ccc1a61d67a4ab)
macOS: version 10.12.6 (build: 16G1212)
logs: /tmp/5EC486D3-0587-483C-A3E7-8024862CBD91/20180309-011820.tar.gz
[OK] vpnkit
[OK] vmnetd
[OK] dns
[OK] driver.amd64-linux
[OK] app
[OK] virtualization VT-X
[OK] moby
[OK] system
[OK] moby-syslog
[OK] kubernetes
[OK] env
[OK] virtualization kern.hv_support
[OK] moby-console
[OK] osxfs
[OK] logs
[OK] docker-cli
[OK] disk
Failure: Could not upload diagnostic data to remote server (docker-diagnose exit code is 1)

You can also run diagnostics manually :
$ /Applications/Docker.app/Contents/Resources/bin/docker-diagnose -u

Steps to reproduce the behavior

1. In Terminal enter:
   docker container export mysql > mysql.tar
2. See the error response

I must say I didn't have this issue about 2 days ago, before I updated Docker.

[guillaumerose]

I can confirm this issue. Here is the dockerd stack trace:

2018-03-12 12:37:17.409021 I | http: panic serving @: runtime error: invalid memory address or nil pointer dereference
goroutine 7405 [running]:
net/http.(*conn).serve.func1(0xc420c099a0)
	/usr/local/go/src/net/http/server.go:1697 +0xd2
panic(0x21655c0, 0x2e71f70)
	/usr/local/go/src/runtime/panic.go:491 +0x287
github.com/docker/docker/daemon.(*Daemon).containerExport(0xc420448240, 0xc420448480, 0x0, 0x0, 0x0, 0x0)
	/go/src/github.com/docker/docker/daemon/export.go:69 +0x31a
github.com/docker/docker/daemon.(*Daemon).ContainerExport(0xc420448240, 0xc4202480d6, 0xc, 0x2e9e020, 0xc42137e000, 0x0, 0x0)
	/go/src/github.com/docker/docker/daemon/export.go:37 +0x2f4
github.com/docker/docker/api/server/router/container.(*containerRouter).getContainersExport(0xc4201343c0, 0x7fcfcd3a53c8, 0xc421b62e40, 0x2eb8be0, 0xc42137e000, 0xc42140e500, 0xc421b62d50, 0x190b3c6, 0x4)
	/go/src/github.com/docker/docker/api/server/router/container/container_routes.go:159 +0xd3
github.com/docker/docker/api/server/router/container.(*containerRouter).(github.com/docker/docker/api/server/router/container.getContainersExport)-fm(0x7fcfcd3a53c8, 0xc421b62e40, 0x2eb8be0, 0xc42137e000, 0xc42140e500, 0xc421b62d50, 0x7fcfcd3a53c8, 0xc421b62e40)
	/go/src/github.com/docker/docker/api/server/router/container/container.go:37 +0x6b
github.com/docker/docker/api/server/middleware.ExperimentalMiddleware.WrapHandler.func1(0x7fcfcd3a53c8, 0xc421b62e40, 0x2eb8be0, 0xc42137e000, 0xc42140e500, 0xc421b62d50, 0x7fcfcd3a53c8, 0xc421b62e40)
	/go/src/github.com/docker/docker/api/server/middleware/experimental.go:27 +0xda
github.com/docker/docker/api/server/middleware.VersionMiddleware.WrapHandler.func1(0x7fcfcd3a53c8, 0xc421b62db0, 0x2eb8be0, 0xc42137e000, 0xc42140e500, 0xc421b62d50, 0xc420248b00, 0xc422326000)
	/go/src/github.com/docker/docker/api/server/middleware/version.go:62 +0x425
github.com/docker/docker/pkg/authorization.(*Middleware).WrapHandler.func1(0x7fcfcd3a53c8, 0xc421b62db0, 0x2eb8be0, 0xc42137e000, 0xc42140e500, 0xc421b62d50, 0x10, 0x401557)
	/go/src/github.com/docker/docker/pkg/authorization/middleware.go:59 +0x83d
github.com/docker/docker/api/server/middleware.DebugRequestMiddleware.func1(0x7fcfcd3a53c8, 0xc421b62db0, 0x2eb8be0, 0xc42137e000, 0xc42140e500, 0xc421b62d50, 0x7fcfcd3a53c8, 0xc421b62db0)
	/go/src/github.com/docker/docker/api/server/middleware/debug.go:22 +0x180
github.com/docker/docker/api/server.(*Server).makeHTTPHandler.func1(0x2eb8be0, 0xc42137e000, 0xc42140e500)
	/go/src/github.com/docker/docker/api/server/server.go:137 +0x1c8
net/http.HandlerFunc.ServeHTTP(0xc420bb9260, 0x2eb8be0, 0xc42137e000, 0xc42140e500)
	/usr/local/go/src/net/http/server.go:1918 +0x46
github.com/docker/docker/vendor/github.com/gorilla/mux.(*Router).ServeHTTP(0xc420b27e00, 0x2eb8be0, 0xc42137e000, 0xc42140e500)
	/go/src/github.com/docker/docker/vendor/github.com/gorilla/mux/mux.go:103 +0x22d
github.com/docker/docker/api/server.(*routerSwapper).ServeHTTP(0xc420db5f00, 0x2eb8be0, 0xc42137e000, 0xc42140e500)
	/go/src/github.com/docker/docker/api/server/router_swapper.go:29 +0x72
net/http.serverHandler.ServeHTTP(0xc420335790, 0x2eb8be0, 0xc42137e000, 0xc42140e500)
	/usr/local/go/src/net/http/server.go:2619 +0xb6
net/http.(*conn).serve(0xc420c099a0, 0x2eba8a0, 0xc421258b00)
	/usr/local/go/src/net/http/server.go:1801 +0x71f
created by net/http.(*Server).Serve
	/usr/local/go/src/net/http/server.go:2720 +0x28a

[thaJeztah]

@guillaumerose what version were you able to reproduce this on? Docker 18.03.0-rc1 on Mac seems to work for me; any particular container/image?

[thaJeztah]

Based on the panic (heard @guillaumerose was on 18.03.0-ce-rc3), I suspect container.BaseFS is nil somehow; https://github.com/docker/docker-ce/blob/v18.03.0-ce-rc3/components/engine/daemon/export.go#L69

[thaJeztah]

I see in daemon.go there's a check for this; https://github.com/moby/moby/blame/1790ce52e96fd66621b5d8eb2e203203874a7921/daemon/daemon.go#L1056

[guillaumerose]

After a reset factory, it works. Is it due to a version upgrade ?

[guillaumerose]

@maltyyev Can you retry to make a diagnostic ? The upload failed for the one you mention.

[maltyyev]

@guillaumerose I'm sorry, it doesn't upload, I don't know why. Is there any other way I can send you diagnostic report?

[vdemeester]

Upstream issue for that : moby/moby#36561 👼

[thaJeztah]

The only location this value is set is in daemon/daemon.go#L1066, and that part of the code won't be reached if the container's RWLayer was not set, or failed to mount daemon/daemon.go#L1047-L1053

I do see one code path where daemon.Mount() can fail, and the error is ignored (only a warning is printed); daemon/daemon.go#L294-L301

[maltyyev]

Ok, reset to factory worked for me too. But now I can't get an image, got unexpected EOF instead =\ This is a really strange situation.
Here is the Terminal output:

docker run hello-world
Unable to find image 'hello-world:latest' locally
latest: Pulling from library/hello-world
ca4f61b1923c: Pulling fs layer
docker: error pulling image configuration: Get https://dseasb33srnrn.cloudfront.net/registry-v2/docker/registry/v2/blobs/sha256/f2/f2a91732366c0332ccd7afd2a5c4ff2b9af81f549370f7a19acd460f87686bc7/data?Expires=1520909211&Signature=GP26HrVDhBARRYod1DFUtqo8HfqhziXBEFVvczr-tzboWHk-dIe4tVdtSvDZn1329qvTEdL5SYYAy6lB4LL1NO7v7BkX-sSRNYpuPDbWpkNx0PDFPI66gqhNXJSEYHe7s6~kG3RuYiCl2pJhq80iNkB9XELTODACy9F20WBAGe8_&Key-Pair-Id=APKAJECH5M7VWIS5YZ6Q: EOF.
See 'docker run --help'.

UPD: If you are wondering how did I manage to export container when I can't download an image, I always have a backup image for mysql on my local drive.
UPD2: It appears to be like I have some problems with an internet. I suppose my provider blocks the URL above for some reason.