当 运行 一个 Docker 容器时主机上没有网络

Question

我在 Arch Linux 机器上，当 运行 使用此命令的容器时主机上没有网络：

docker run jenkins

停止 Docker 后，网络又恢复了。 欢迎任何建议。

编辑：

似乎当 运行 -p 选项并提供 80 以外的其他端口时，网络可用几分钟，然后再次丢失。

**> docker version**

Client:
 Version:      1.9.1
 API version:  1.21
 Go version:   go1.5.1
 Git commit:   a34a1d5-dirty
 Built:        Sun Nov 22 00:15:15 UTC 2015
 OS/Arch:      linux/amd64

Server:
 Version:      1.9.1
 API version:  1.21
 Go version:   go1.5.1
 Git commit:   a34a1d5-dirty
 Built:        Sun Nov 22 00:15:15 UTC 2015
 OS/Arch:      linux/amd64

**> docker info**

Containers: 31
Images: 57
Server Version: 1.9.1
Storage Driver: devicemapper
 Pool Name: docker-8:5-548039-pool
 Pool Blocksize: 65.54 kB
 Base Device Size: 107.4 GB
 Backing Filesystem: 
 Data file: /dev/loop0
 Metadata file: /dev/loop1
 Data Space Used: 3.584 GB
 Data Space Total: 107.4 GB
 Data Space Available: 7.741 GB
 Metadata Space Used: 7.496 MB
 Metadata Space Total: 2.147 GB
 Metadata Space Available: 2.14 GB
 Udev Sync Supported: true
 Deferred Removal Enabled: false
 Deferred Deletion Enabled: false
 Deferred Deleted Device Count: 0
 Data loop file: /var/lib/docker/devicemapper/devicemapper/data
 Metadata loop file: /var/lib/docker/devicemapper/devicemapper/metadata
 Library Version: 1.02.113 (2015-12-05)
Execution Driver: native-0.2
Logging Driver: json-file
Kernel Version: 4.2.5-1-ARCH
Operating System: Arch Linux (containerized)
CPUs: 4
Total Memory: 7.709 GiB
Name: arch
ID: OF5Y:H7O4:M4R6:GCF6:NSEU:LNG6:K7NV:FJDM:DUVI:6KOM:LTRB:EUPP

> iptables -L

Chain INPUT (policy ACCEPT)
target     prot opt source               destination         

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         
DOCKER     all  --  anywhere             anywhere            
ACCEPT     all  --  anywhere             anywhere             ctstate RELATED,ESTABLISHED
ACCEPT     all  --  anywhere             anywhere            
ACCEPT     all  --  anywhere             anywhere            

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         

Chain DOCKER (1 references)
target     prot opt source               destination         

Answer 1

可能是您的 docker 主机网络设置不适合 Docker。试试 Docker 文档中的 Arch Linux specific instructions regarding networking：

If you manually configure your network using systemd-network version 220 or higher, containers you start with Docker may be unable to access your network. Beginning with version 220, the forwarding setting for a given network (net.ipv4.conf.<interface>.forwarding) defaults to off. This setting prevents IP forwarding. It also conflicts with Docker which enables the net.ipv4.conf.all.forwarding setting within a container.

To work around this, edit the <interface>.network file in /etc/systemd/network/ on your Docker host add > the following block:

[Network]
...
IPForward=kernel
...

This configuration allows IP forwarding from the container as expected.

---

也可以尝试 Arch Linux wiki 中关于 Docker 的 docker0 Bridge gets no IP / no internet access in containers 部分：

Docker enables IP forwarding by itself, but by default systemd overrides the respective sysctl setting. The following disables this override (for all interfaces):

# cat > /etc/systemd/network/ipforward.network <<EOF
[Network]
IPForward=ipv4
EOF

# cat > /etc/systemd/network/99-docker.conf <<EOF
net.ipv4.ip_forward = 1
EOF

# sysctl -w net.ipv4.ip_forward=1

Finally restart the systemd-networkd and docker services.

Answer 2

解决方案是使用以下内容创建或编辑 /etc/connman/main.conf：

[General]
NetworkInterfaceBlacklist=vmnet,vboxnet,virbr,ifb,docker,veth,eth,wlan

并重启connman。

如described here.