Updating networking docs with technical information
- the /etc/hosts read caveat due to dynamic update - information about docker_gwbridge - Carries and closes #17654 - Updating with last change by Madhu - Updating with the IPAM api 1.22 Signed-off-by: Mary Anthony <mary@docker.com>
This commit is contained in:
Madhu Venugopal
Mary Anthony
parent
8d5695470a
commit
39dfc536d4
5 changed files with 193 additions and 93 deletions
|
|
@ -2715,6 +2715,12 @@ Content-Type: application/json
|
|||
{
|
||||
"Name":"isolated_nw",
|
||||
"Driver":"bridge"
|
||||
"IPAM":{
|
||||
"Config":[{
|
||||
"Subnet":"172.20.0.0/16",
|
||||
"IPRange":"172.20.10.0/24",
|
||||
"Gateway":"172.20.10.11"
|
||||
}]
|
||||
}
|
||||
```
|
||||
|
||||
|
|
@ -2740,6 +2746,7 @@ JSON Parameters:
|
|||
|
||||
- **Name** - The new network's name. this is a mandatory field
|
||||
- **Driver** - Name of the network driver to use. Defaults to `bridge` driver
|
||||
- **IPAM** - Optional custom IP scheme for the network
|
||||
- **Options** - Network specific options to be used by the drivers
|
||||
- **CheckDuplicate** - Requests daemon to check for networks with same name
|
||||
|
||||
|
|
|
|||
|
|
@ -2709,6 +2709,11 @@ Create a network
|
|||
|
||||
**Example request**:
|
||||
|
||||
```
|
||||
Create a network
|
||||
|
||||
**Example request**:
|
||||
|
||||
```
|
||||
POST /networks/create HTTP/1.1
|
||||
Content-Type: application/json
|
||||
|
|
@ -2716,6 +2721,12 @@ Content-Type: application/json
|
|||
{
|
||||
"Name":"isolated_nw",
|
||||
"Driver":"bridge"
|
||||
"IPAM":{
|
||||
"Config":[{
|
||||
"Subnet":"172.20.0.0/16",
|
||||
"IPRange":"172.20.10.0/24",
|
||||
"Gateway":"172.20.10.11"
|
||||
}]
|
||||
}
|
||||
```
|
||||
|
||||
|
|
@ -2741,6 +2752,7 @@ JSON Parameters:
|
|||
|
||||
- **Name** - The new network's name. this is a mandatory field
|
||||
- **Driver** - Name of the network driver to use. Defaults to `bridge` driver
|
||||
- **IPAM** - Optional custom IP scheme for the network
|
||||
- **Options** - Network specific options to be used by the drivers
|
||||
- **CheckDuplicate** - Requests daemon to check for networks with same name
|
||||
|
||||
|
|
|
|||
|
|
@ -404,6 +404,19 @@ container itself as well as `localhost` and a few other common things. The
|
|||
::1 localhost ip6-localhost ip6-loopback
|
||||
86.75.30.9 db-static
|
||||
|
||||
If a container is connected to the default bridge network and `linked`
|
||||
with other containers, then the container's `/etc/hosts` file is updated
|
||||
with the linked container's name.
|
||||
|
||||
If the container is connected to user-defined network, the container's
|
||||
`/etc/hosts` file is updated with names of all other containers in that
|
||||
user-defined network.
|
||||
|
||||
> **Note** Since Docker may live update the container’s `/etc/hosts` file, there
|
||||
may be situations when processes inside the container can end up reading an
|
||||
empty or incomplete `/etc/hosts` file. In most cases, retrying the read again
|
||||
should fix the problem.
|
||||
|
||||
## Restart policies (--restart)
|
||||
|
||||
Using the `--restart` flag on Docker run you can specify a restart policy for
|
||||
|
|
|
|||
|
|
@ -11,7 +11,7 @@ weight=-3
|
|||
|
||||
# Get started with multi-host networking
|
||||
|
||||
This article uses an example to explain the basics of creating a mult-host
|
||||
This article uses an example to explain the basics of creating a multi-host
|
||||
network. Docker Engine supports multi-host-networking out-of-the-box through the
|
||||
`overlay` network driver. Unlike `bridge` networks overlay networks require
|
||||
some pre-existing conditions before you can create one. These conditions are:
|
||||
|
|
@ -21,8 +21,10 @@ some pre-existing conditions before you can create one. These conditions are:
|
|||
* A cluster of hosts with connectivity to the key-value store.
|
||||
* A properly configured Engine `daemon` on each host in the cluster.
|
||||
|
||||
You'll use Docker Machine to create both the the key-value store server and the
|
||||
host cluster. This example creates a Swarm cluster.
|
||||
Though Docker Machine and Docker Swarm are not mandatory to experience Docker
|
||||
multi-host-networking, this example uses them to illustrate how they are
|
||||
integrated. You'll use Machine to create both the the key-value store
|
||||
server and the host cluster. This example creates a Swarm cluster.
|
||||
|
||||
## Prerequisites
|
||||
|
||||
|
|
@ -46,7 +48,7 @@ store) key-value stores. This example uses Consul.
|
|||
|
||||
2. Provision a VirtualBox machine called `mh-keystore`.
|
||||
|
||||
$ docker-machine create -d virtualbox mh-keystore
|
||||
$ docker-machine create -d virtualbox mh-keystore
|
||||
|
||||
When you provision a new machine, the process adds Docker Engine to the
|
||||
host. This means rather than installing Consul manually, you can create an
|
||||
|
|
@ -55,10 +57,10 @@ store) key-value stores. This example uses Consul.
|
|||
|
||||
3. Start a `progrium/consul` container running on the `mh-keystore` machine.
|
||||
|
||||
$ docker $(docker-machine config mh-keystore) run -d \
|
||||
-p "8500:8500" \
|
||||
-h "consul" \
|
||||
progrium/consul -server -bootstrap
|
||||
$ docker $(docker-machine config mh-keystore) run -d \
|
||||
-p "8500:8500" \
|
||||
-h "consul" \
|
||||
progrium/consul -server -bootstrap
|
||||
|
||||
You passed the `docker run` command the connection configuration using a bash
|
||||
expansion `$(docker-machine config mh-keystore)`. The client started a
|
||||
|
|
@ -66,13 +68,13 @@ store) key-value stores. This example uses Consul.
|
|||
|
||||
4. Set your local environment to the `mh-keystore` machine.
|
||||
|
||||
$ eval "$(docker-machine env mh-keystore)"
|
||||
$ eval "$(docker-machine env mh-keystore)"
|
||||
|
||||
5. Run the `docker ps` command to see the `consul` container.
|
||||
|
||||
$ docker ps
|
||||
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
|
||||
4d51392253b3 progrium/consul "/bin/start -server -" 25 minutes ago Up 25 minutes 53/tcp, 53/udp, 8300-8302/tcp, 0.0.0.0:8500->8500/tcp, 8400/tcp, 8301-8302/udp admiring_panini
|
||||
$ docker ps
|
||||
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
|
||||
4d51392253b3 progrium/consul "/bin/start -server -" 25 minutes ago Up 25 minutes 53/tcp, 53/udp, 8300-8302/tcp, 0.0.0.0:8500->8500/tcp, 8400/tcp, 8301-8302/udp admiring_panini
|
||||
|
||||
Keep your terminal open and move onto the next step.
|
||||
|
||||
|
|
@ -87,13 +89,13 @@ that machine options that are needed by the `overlay` network driver.
|
|||
|
||||
1. Create a Swarm master.
|
||||
|
||||
$ docker-machine create \
|
||||
-d virtualbox \
|
||||
--swarm --swarm-image="swarm" --swarm-master \
|
||||
--swarm-discovery="consul://$(docker-machine ip mh-keystore):8500" \
|
||||
--engine-opt="cluster-store=consul://$(docker-machine ip mh-keystore):8500" \
|
||||
--engine-opt="cluster-advertise=eth1:2376" \
|
||||
mhs-demo0
|
||||
$ docker-machine create \
|
||||
-d virtualbox \
|
||||
--swarm --swarm-image="swarm" --swarm-master \
|
||||
--swarm-discovery="consul://$(docker-machine ip mh-keystore):8500" \
|
||||
--engine-opt="cluster-store=consul://$(docker-machine ip mh-keystore):8500" \
|
||||
--engine-opt="cluster-advertise=eth1:2376" \
|
||||
mhs-demo0
|
||||
|
||||
At creation time, you supply the Engine `daemon` with the ` --cluster-store` option. This option tells the Engine the location of the key-value store for the `overlay` network. The bash expansion `$(docker-machine ip mh-keystore)` resolves to the IP address of the Consul server you created in "STEP 1". The `--cluster-advertise` option advertises the machine on the network.
|
||||
|
||||
|
|
@ -126,74 +128,71 @@ To create an overlay network
|
|||
|
||||
1. Set your docker environment to the Swarm master.
|
||||
|
||||
$ eval $(docker-machine env --swarm mhs-demo0)
|
||||
$ eval $(docker-machine env --swarm mhs-demo0)
|
||||
|
||||
Using the `--swarm` flag with `docker-machine` restricts the `docker` commands to Swarm information alone.
|
||||
Using the `--swarm` flag with `docker-machine` restricts the `docker` commands to Swarm information alone.
|
||||
|
||||
2. Use the `docker info` command to view the Swarm.
|
||||
|
||||
$ docker info
|
||||
Containers: 3
|
||||
Images: 2
|
||||
Role: primary
|
||||
Strategy: spread
|
||||
Filters: affinity, health, constraint, port, dependency
|
||||
Nodes: 2
|
||||
mhs-demo0: 192.168.99.104:2376
|
||||
└ Containers: 2
|
||||
└ Reserved CPUs: 0 / 1
|
||||
└ Reserved Memory: 0 B / 1.021 GiB
|
||||
└ Labels: executiondriver=native-0.2, kernelversion=4.1.10-boot2docker, operatingsystem=Boot2Docker 1.9.0-rc1 (TCL 6.4); master : 4187d2c - Wed Oct 14 14:00:28 UTC 2015, provider=virtualbox, storagedriver=aufs
|
||||
mhs-demo1: 192.168.99.105:2376
|
||||
└ Containers: 1
|
||||
└ Reserved CPUs: 0 / 1
|
||||
└ Reserved Memory: 0 B / 1.021 GiB
|
||||
└ Labels: executiondriver=native-0.2, kernelversion=4.1.10-boot2docker, operatingsystem=Boot2Docker 1.9.0-rc1 (TCL 6.4); master : 4187d2c - Wed Oct 14 14:00:28 UTC 2015, provider=virtualbox, storagedriver=aufs
|
||||
CPUs: 2
|
||||
Total Memory: 2.043 GiB
|
||||
Name: 30438ece0915
|
||||
$ docker info
|
||||
Containers: 3
|
||||
Images: 2
|
||||
Role: primary
|
||||
Strategy: spread
|
||||
Filters: affinity, health, constraint, port, dependency
|
||||
Nodes: 2
|
||||
mhs-demo0: 192.168.99.104:2376
|
||||
└ Containers: 2
|
||||
└ Reserved CPUs: 0 / 1
|
||||
└ Reserved Memory: 0 B / 1.021 GiB
|
||||
└ Labels: executiondriver=native-0.2, kernelversion=4.1.10-boot2docker, operatingsystem=Boot2Docker 1.9.0-rc1 (TCL 6.4); master : 4187d2c - Wed Oct 14 14:00:28 UTC 2015, provider=virtualbox, storagedriver=aufs
|
||||
mhs-demo1: 192.168.99.105:2376
|
||||
└ Containers: 1
|
||||
└ Reserved CPUs: 0 / 1
|
||||
└ Reserved Memory: 0 B / 1.021 GiB
|
||||
└ Labels: executiondriver=native-0.2, kernelversion=4.1.10-boot2docker, operatingsystem=Boot2Docker 1.9.0-rc1 (TCL 6.4); master : 4187d2c - Wed Oct 14 14:00:28 UTC 2015, provider=virtualbox, storagedriver=aufs
|
||||
CPUs: 2
|
||||
Total Memory: 2.043 GiB
|
||||
Name: 30438ece0915
|
||||
|
||||
From this information, you can see that you are running three containers and 2 images on the Master.
|
||||
|
||||
3. Create your `overlay` network.
|
||||
|
||||
$ docker network create --driver overlay my-net
|
||||
$ docker network create --driver overlay my-net
|
||||
|
||||
You only need to create the network on a single host in the cluster. In this case, you used the Swarm master but you could easily have run it on any host in the cluster.
|
||||
You only need to create the network on a single host in the cluster. In this case, you used the Swarm master but you could easily have run it on any host in the cluster.
|
||||
|
||||
4. Check that the network is running:
|
||||
|
||||
$ docker network ls
|
||||
NETWORK ID NAME DRIVER
|
||||
412c2496d0eb mhs-demo1/host host
|
||||
dd51763e6dd2 mhs-demo0/bridge bridge
|
||||
6b07d0be843f my-net overlay
|
||||
b4234109bd9b mhs-demo0/none null
|
||||
1aeead6dd890 mhs-demo0/host host
|
||||
d0bb78cbe7bd mhs-demo1/bridge bridge
|
||||
1c0eb8f69ebb mhs-demo1/none null
|
||||
$ docker network ls
|
||||
NETWORK ID NAME DRIVER
|
||||
412c2496d0eb mhs-demo1/host host
|
||||
dd51763e6dd2 mhs-demo0/bridge bridge
|
||||
6b07d0be843f my-net overlay
|
||||
b4234109bd9b mhs-demo0/none null
|
||||
1aeead6dd890 mhs-demo0/host host
|
||||
d0bb78cbe7bd mhs-demo1/bridge bridge
|
||||
1c0eb8f69ebb mhs-demo1/none null
|
||||
|
||||
Because you are in the Swarm master environment, you see all the networks on all Swarm agents. Notice that each `NETWORK ID` is unique. The default networks on each engine and the single overlay network.
|
||||
|
||||
5. Switch to each Swarm agent in turn and list the network.
|
||||
|
||||
$ eval $(docker-machine env mhs-demo0)
|
||||
|
||||
$ docker network ls
|
||||
NETWORK ID NAME DRIVER
|
||||
6b07d0be843f my-net overlay
|
||||
dd51763e6dd2 bridge bridge
|
||||
b4234109bd9b none null
|
||||
1aeead6dd890 host host
|
||||
|
||||
$ eval $(docker-machine env mhs-demo1)
|
||||
|
||||
$ docker network ls
|
||||
NETWORK ID NAME DRIVER
|
||||
d0bb78cbe7bd bridge bridge
|
||||
1c0eb8f69ebb none null
|
||||
412c2496d0eb host host
|
||||
6b07d0be843f my-net overlay
|
||||
$ eval $(docker-machine env mhs-demo0)
|
||||
$ docker network ls
|
||||
NETWORK ID NAME DRIVER
|
||||
6b07d0be843f my-net overlay
|
||||
dd51763e6dd2 bridge bridge
|
||||
b4234109bd9b none null
|
||||
1aeead6dd890 host host
|
||||
$ eval $(docker-machine env mhs-demo1)
|
||||
$ docker network ls
|
||||
NETWORK ID NAME DRIVER
|
||||
d0bb78cbe7bd bridge bridge
|
||||
1c0eb8f69ebb none null
|
||||
412c2496d0eb host host
|
||||
6b07d0be843f my-net overlay
|
||||
|
||||
Both agents reports it has the `my-net `network with the `6b07d0be843f` id. You have a multi-host container network running!
|
||||
|
||||
|
|
@ -203,7 +202,7 @@ Once your network is created, you can start a container on any of the hosts and
|
|||
|
||||
1. Point your environment to your `mhs-demo0` instance.
|
||||
|
||||
$ eval $(docker-machine env mhs-demo0)
|
||||
$ eval $(docker-machine env mhs-demo0)
|
||||
|
||||
2. Start an Nginx server on `mhs-demo0`.
|
||||
|
||||
|
|
@ -215,7 +214,7 @@ Once your network is created, you can start a container on any of the hosts and
|
|||
|
||||
$ eval $(docker-machine env mhs-demo1)
|
||||
|
||||
2. Run a Busybox instance and get the contents of the Ngnix server's home page.
|
||||
4. Run a Busybox instance and get the contents of the Ngnix server's home page.
|
||||
|
||||
$ docker run -it --rm --net=my-net --env="constraint:node==mhs-demo1" busybox wget -O- http://web
|
||||
Unable to find image 'busybox:latest' locally
|
||||
|
|
@ -252,9 +251,68 @@ Once your network is created, you can start a container on any of the hosts and
|
|||
</html>
|
||||
- 100% |*******************************| 612 0:00:00 ETA
|
||||
|
||||
## Step 5: Extra Credit with Docker Compose
|
||||
## Step 5: Check external connectivity
|
||||
|
||||
You can try starting a second network on your existing Swarm cluser using Docker Compose.
|
||||
As you've seen, Docker's built-in overlay network driver provides out-of-the-box
|
||||
connectivity between the containers on multiple hosts within the same network.
|
||||
Additionally, containers connected to the multi-host network are automatically
|
||||
connected to the `docker_gwbridge` network. This network allows the containers
|
||||
to have external connectivity outside of their cluster.
|
||||
|
||||
1. Change your environment to the Swarm agent.
|
||||
|
||||
$ eval $(docker-machine env mhs-demo1)
|
||||
|
||||
2. View the `docker_gwbridge` network, by listing the networks.
|
||||
|
||||
$ docker network ls
|
||||
NETWORK ID NAME DRIVER
|
||||
6b07d0be843f my-net overlay
|
||||
dd51763e6dd2 bridge bridge
|
||||
b4234109bd9b none null
|
||||
1aeead6dd890 host host
|
||||
e1dbd5dff8be docker_gwbridge bridge
|
||||
|
||||
3. Repeat steps 1 and 2 on the Swarm master.
|
||||
|
||||
$ eval $(docker-machine env mhs-demo0)
|
||||
$ docker network ls
|
||||
NETWORK ID NAME DRIVER
|
||||
6b07d0be843f my-net overlay
|
||||
d0bb78cbe7bd bridge bridge
|
||||
1c0eb8f69ebb none null
|
||||
412c2496d0eb host host
|
||||
97102a22e8d2 docker_gwbridge bridge
|
||||
|
||||
2. Check the Ngnix container's network interfaces.
|
||||
|
||||
$ docker exec web ip addr
|
||||
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default
|
||||
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
|
||||
inet 127.0.0.1/8 scope host lo
|
||||
valid_lft forever preferred_lft forever
|
||||
inet6 ::1/128 scope host
|
||||
valid_lft forever preferred_lft forever
|
||||
22: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UP group default
|
||||
link/ether 02:42:0a:00:09:03 brd ff:ff:ff:ff:ff:ff
|
||||
inet 10.0.9.3/24 scope global eth0
|
||||
valid_lft forever preferred_lft forever
|
||||
inet6 fe80::42:aff:fe00:903/64 scope link
|
||||
valid_lft forever preferred_lft forever
|
||||
24: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
|
||||
link/ether 02:42:ac:12:00:02 brd ff:ff:ff:ff:ff:ff
|
||||
inet 172.18.0.2/16 scope global eth1
|
||||
valid_lft forever preferred_lft forever
|
||||
inet6 fe80::42:acff:fe12:2/64 scope link
|
||||
valid_lft forever preferred_lft forever
|
||||
|
||||
The `eth0` interface represents the container interface that is connected to
|
||||
the `my-net` overlay network. While the `eth1` interface represents the
|
||||
container interface that is connected to the `docker_gwbridge` network.
|
||||
|
||||
## Step 6: Extra Credit with Docker Compose
|
||||
|
||||
You can try starting a second network on your existing Swarm cluster using Docker Compose.
|
||||
|
||||
1. Log into the Swarm master.
|
||||
|
||||
|
|
@ -271,7 +329,6 @@ You can try starting a second network on your existing Swarm cluser using Docker
|
|||
- "constraint:node==swl-demo0"
|
||||
ports:
|
||||
- "80:5000"
|
||||
|
||||
mongo:
|
||||
image: mongo
|
||||
|
||||
|
|
@ -283,5 +340,7 @@ You can try starting a second network on your existing Swarm cluser using Docker
|
|||
|
||||
## Related information
|
||||
|
||||
* [Understand Docker container networks](dockernetworks.md)
|
||||
* [Work with network commands](work-with-networks.md)
|
||||
* [Docker Swarm overview](https://docs.docker.com/swarm)
|
||||
* [Docker Machine overview](https://docs.docker.com/machine)
|
||||
|
|
|
|||
|
|
@ -355,9 +355,9 @@ ports and the exposed ports, use `docker port`.
|
|||
Publish a container's port, or range of ports, to the host.
|
||||
|
||||
Format: `ip:hostPort:containerPort | ip::containerPort | hostPort:containerPort | containerPort`
|
||||
Both hostPort and containerPort can be specified as a range of ports.
|
||||
Both hostPort and containerPort can be specified as a range of ports.
|
||||
When specifying ranges for both, the number of container ports in the range must match the number of host ports in the range.
|
||||
(e.g., `docker run -p 1234-1236:1222-1224 --name thisWorks -t busybox`
|
||||
(e.g., `docker run -p 1234-1236:1222-1224 --name thisWorks -t busybox`
|
||||
but not `docker run -p 1230-1236:1230-1240 --name RangeContainerPortsBiggerThanRangeHostPorts -t busybox`)
|
||||
With ip: `docker run -p 127.0.0.1:$HOSTPORT:$CONTAINERPORT --name CONTAINER -t someimage`
|
||||
Use `docker port` to see the actual mapping: `docker port CONTAINER $CONTAINERPORT`
|
||||
|
|
@ -437,17 +437,17 @@ standard input.
|
|||
""--ulimit""=[]
|
||||
Ulimit options
|
||||
|
||||
**-v**, **--volume**=[] Create a bind mount
|
||||
**-v**, **--volume**=[] Create a bind mount
|
||||
(format: `[host-dir:]container-dir[:<suffix options>]`, where suffix options
|
||||
are comma delimited and selected from [rw|ro] and [z|Z].)
|
||||
|
||||
|
||||
(e.g., using -v /host-dir:/container-dir, bind mounts /host-dir in the
|
||||
host to /container-dir in the Docker container)
|
||||
|
||||
|
||||
If 'host-dir' is missing, then docker automatically creates the new volume
|
||||
on the host. **This auto-creation of the host path has been deprecated in
|
||||
Release: v1.9.**
|
||||
|
||||
|
||||
The **-v** option can be used one or
|
||||
more times to add one or more mounts to a container. These mounts can then be
|
||||
used in other containers using the **--volumes-from** option.
|
||||
|
|
@ -469,31 +469,31 @@ content label. Shared volume labels allow all containers to read/write content.
|
|||
The `Z` option tells Docker to label the content with a private unshared label.
|
||||
Only the current container can use a private volume.
|
||||
|
||||
The `container-dir` must always be an absolute path such as `/src/docs`.
|
||||
The `host-dir` can either be an absolute path or a `name` value. If you
|
||||
supply an absolute path for the `host-dir`, Docker bind-mounts to the path
|
||||
The `container-dir` must always be an absolute path such as `/src/docs`.
|
||||
The `host-dir` can either be an absolute path or a `name` value. If you
|
||||
supply an absolute path for the `host-dir`, Docker bind-mounts to the path
|
||||
you specify. If you supply a `name`, Docker creates a named volume by that `name`.
|
||||
|
||||
A `name` value must start with start with an alphanumeric character,
|
||||
followed by `a-z0-9`, `_` (underscore), `.` (period) or `-` (hyphen).
|
||||
A `name` value must start with start with an alphanumeric character,
|
||||
followed by `a-z0-9`, `_` (underscore), `.` (period) or `-` (hyphen).
|
||||
An absolute path starts with a `/` (forward slash).
|
||||
|
||||
For example, you can specify either `/foo` or `foo` for a `host-dir` value.
|
||||
If you supply the `/foo` value, Docker creates a bind-mount. If you supply
|
||||
For example, you can specify either `/foo` or `foo` for a `host-dir` value.
|
||||
If you supply the `/foo` value, Docker creates a bind-mount. If you supply
|
||||
the `foo` specification, Docker creates a named volume.
|
||||
|
||||
**--volumes-from**=[]
|
||||
Mount volumes from the specified container(s)
|
||||
|
||||
Mounts already mounted volumes from a source container onto another
|
||||
container. You must supply the source's container-id. To share
|
||||
container. You must supply the source's container-id. To share
|
||||
a volume, use the **--volumes-from** option when running
|
||||
the target container. You can share volumes even if the source container
|
||||
the target container. You can share volumes even if the source container
|
||||
is not running.
|
||||
|
||||
By default, Docker mounts the volumes in the same mode (read-write or
|
||||
read-only) as it is mounted in the source container. Optionally, you
|
||||
can change this by suffixing the container-id with either the `:ro` or
|
||||
By default, Docker mounts the volumes in the same mode (read-write or
|
||||
read-only) as it is mounted in the source container. Optionally, you
|
||||
can change this by suffixing the container-id with either the `:ro` or
|
||||
`:rw ` keyword.
|
||||
|
||||
If the location of the volume from the source container overlaps with
|
||||
|
|
@ -558,7 +558,7 @@ Now run a regular container, and it correctly does NOT see the shared memory seg
|
|||
```
|
||||
$ docker run -it shm ipcs -m
|
||||
|
||||
------ Shared Memory Segments --------
|
||||
------ Shared Memory Segments --------
|
||||
key shmid owner perms bytes nattch status
|
||||
```
|
||||
|
||||
|
|
@ -637,6 +637,15 @@ Running the **env** command in the linker container shows environment variables
|
|||
When linking two containers Docker will use the exposed ports of the container
|
||||
to create a secure tunnel for the parent to access.
|
||||
|
||||
If a container is connected to the default bridge network and `linked`
|
||||
with other containers, then the container's `/etc/hosts` file is updated
|
||||
with the linked container's name.
|
||||
|
||||
> **Note** Since Docker may live update the container’s `/etc/hosts` file, there
|
||||
may be situations when processes inside the container can end up reading an
|
||||
empty or incomplete `/etc/hosts` file. In most cases, retrying the read again
|
||||
should fix the problem.
|
||||
|
||||
|
||||
## Mapping Ports for External Usage
|
||||
|
||||
|
|
|
|||
Loading…
Reference in a new issue