Static Routing Challenge
In the previous class, we’ve used the following network topology.
This guide explains how to extend the topology.
Table of Contents
- Step 1: Create the Network
- Step 2: Create the Host (Container)
- Step 3: Connect between a host (Container) and a network
Step 1: Create the Network
To create the network, use the following command:
$ docker network create <network_name> -d bridge --subnet=<subnet>
To check whether it’s created or not, use the following command:
$ docker network ls
To remove networks, use the following command:
$ docker network rm <network_name> <network_name>
Example
To add a new network named nw59 whose subnet is 192.168.59.0/24, type like this:
$ docker network create nw59 -d bridge --subnet=192.168.59.0/24
The topology will like as below.
Here is an example of adding and removing a network named nw59.
$ docker network ls
NETWORK ID NAME DRIVER SCOPE
a1aea284a91a bridge bridge local
3a05f05787c9 host host local
3cd75e5b104d none null local
6361b594a881 nw56 bridge local
d98813a74c43 nw57 bridge local
d9e438cba1b3 nw58 bridge local
$ docker network create nw59 -d bridge --subnet=192.168.59.0/24
7a38c2a32e90bc7fa8a3974f9cbc119cb8031461e56144e387ad1dbeb5fdfb99
$ docker network ls
NETWORK ID NAME DRIVER SCOPE
a1aea284a91a bridge bridge local
3a05f05787c9 host host local
3cd75e5b104d none null local
6361b594a881 nw56 bridge local
d98813a74c43 nw57 bridge local
d9e438cba1b3 nw58 bridge local
7a38c2a32e90 nw59 bridge local
$ docker network rm nw59
nw59
$ docker network ls
NETWORK ID NAME DRIVER SCOPE
a1aea284a91a bridge bridge local
3a05f05787c9 host host local
3cd75e5b104d none null local
6361b594a881 nw56 bridge local
d98813a74c43 nw57 bridge local
d9e438cba1b3 nw58 bridge local
Step 2: Create the Host (Container)
To create the host (Container), use the following command:
$ docker create -it --name=<container_name> --net=<network_name> --cap-add=NET_ADMIN --ip=<ip address> ieng /bin/bash
After that, you need to start its container.
YOU CAN’T SPECIFY THE IP OF WHICH THE LAST BYTE IS ONE LIKE 192.168.59.1.
This is due to specification of the docker.
To check whether it’s created or not, use the following command:
$ docker container ls --all
To remove the host (Container), use the following command:
$ docker container rm <container_name>
Before this, you need to stop its container. Or you can use --force argument like this:
$ docker container rm <container_name> --force
Example
To create a container named hostE whose ip address is 192.168.59.2 whose network is nw59, type like this:
$ docker create -it --name=hostE --net=nw59 --cap-add=NET_ADMIN --ip=192.168.59.2 ieng /bin/bash
The topology will like as below. This topology has already applied to Step 1.
Here is an example of creating and attaching and detaching and removing a container named hostE.
$ docker container ls --all
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
f894d04b5e7e ieng "/bin/bash" 6 days ago Exited (0) 6 days ago hostD
d39fdce4f635 ieng "/bin/bash" 6 days ago Exited (0) 6 days ago hostC
b78f6d49437c ieng "/bin/bash" 6 days ago Exited (0) 6 days ago hostB
bb46dbffbfad ieng "/bin/bash" 6 days ago Exited (0) 6 days ago hostA
$ docker create -it --name=hostE --net=nw59 --cap-add=NET_ADMIN --ip=192.168.59.2 ieng /bin/bash
11873b72f6391a9e797092b09f61f5967f49e1610e7d682a44d706a9d5011959
$ docker container ls --all
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
11873b72f639 ieng "/bin/bash" 4 seconds ago Created hostE
f894d04b5e7e ieng "/bin/bash" 6 days ago Exited (0) 6 days ago hostD
d39fdce4f635 ieng "/bin/bash" 6 days ago Exited (0) 6 days ago hostC
b78f6d49437c ieng "/bin/bash" 6 days ago Exited (0) 6 days ago hostB
bb46dbffbfad ieng "/bin/bash" 6 days ago Exited (0) 6 days ago hostA
$ docker start hostE
hostE
$ docker attach hostE
ieng@11873b72f639:~$ read escape sequence
$ docker rm hostE
Error response from daemon: You cannot remove a running container 11873b72f6391a9e797092b09f61f5967f49e1610e7d682a44d706a9d5011959. Stop the container before attempting removal or force remove
$ docker stop hostE
hostE
$ docker rm hostE
hostE
read escape sequence means I pressed CTRL - P and CTRL - Q (detaching the container).
As you can see, you have to stop the container before removing. But with --force argument, you can remove it.
Step 3: Connect between a host (Container) and a network
To connect between a host (Container) and a network, use the following command:
$ docker network connect <network_name> <container_name>
To disconnect between a host (Container) and a network, use the following command:
$ docker network disconnect <network_name> <container_name>
To check whether it’s connected or not, use the following command:
$ docker inspect <container_name>
You can also specify <network_name>, but you won’t check whether it’s connected by hostE or not.
The output is too long. It’s good idea to filter output to Networks by using grep.
To check an ip address or network interface, start and attach its container, and then use the following command:
$ ip a
Example
To connect between nw59 and hostB, type like this:
$ docker network connect nw59 hostB
The topology will like as below. This topology has already applied to Step 1 and 2.
Here is an example of connecting and checking (by docker inspect and ip a) and disconnecting between nw59 and hostB.
$ docker start hostB
hostB
$ docker attach hostB
ieng@b78f6d49437c:~$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
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
14: eth1@if15: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:c0:a8:3a:02 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet 192.168.58.2/24 brd 192.168.58.255 scope global eth1
valid_lft forever preferred_lft forever
18: eth0@if19: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:c0:a8:38:03 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet 192.168.56.3/24 brd 192.168.56.255 scope global eth0
valid_lft forever preferred_lft forever
ieng@b78f6d49437c:~$ read escape sequence
$ docker inspect hostB | grep Networks -A 100
"Networks": {
"nw56": {
"IPAMConfig": {
"IPv4Address": "192.168.56.3"
},
"Links": null,
"Aliases": [
"b78f6d49437c"
],
"NetworkID": "6361b594a881ead174967e117fe821ddfc9c6085946282b46fa45b789da48b15",
"EndpointID": "11fa755819a59d75f30a0e14dc837aed6d4c073b659f457c335de00f2a7c25b4",
"Gateway": "192.168.56.1",
"IPAddress": "192.168.56.3",
"IPPrefixLen": 24,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "02:42:c0:a8:38:03",
"DriverOpts": null
},
"nw58": {
"IPAMConfig": {
"IPv4Address": "192.168.58.2"
},
"Links": null,
"Aliases": [
"b78f6d49437c"
],
"NetworkID": "d9e438cba1b35a0d37cd167fa572a4bf8bbf896592fcff7e52c843c55ef18316",
"EndpointID": "ad97fc0248583ba0c027cd04d202db5f5dd6c5b53d3229acfab1327f03819cc1",
"Gateway": "192.168.58.1",
"IPAddress": "192.168.58.2",
"IPPrefixLen": 24,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "02:42:c0:a8:3a:02",
"DriverOpts": null
}
}
}
}
]
$ docker network connect nw59 hostB
$ docker inspect hostB | grep Networks -A 100
"Networks": {
"nw56": {
"IPAMConfig": {
"IPv4Address": "192.168.56.3"
},
"Links": null,
"Aliases": [
"b78f6d49437c"
],
"NetworkID": "6361b594a881ead174967e117fe821ddfc9c6085946282b46fa45b789da48b15",
"EndpointID": "",
"Gateway": "",
"IPAddress": "",
"IPPrefixLen": 0,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "",
"DriverOpts": null
},
"nw58": {
"IPAMConfig": {
"IPv4Address": "192.168.58.2"
},
"Links": null,
"Aliases": [
"b78f6d49437c"
],
"NetworkID": "d9e438cba1b35a0d37cd167fa572a4bf8bbf896592fcff7e52c843c55ef18316",
"EndpointID": "",
"Gateway": "",
"IPAddress": "",
"IPPrefixLen": 0,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "",
"DriverOpts": null
},
"nw59": {
"IPAMConfig": {},
"Links": null,
"Aliases": [
"b78f6d49437c"
],
"NetworkID": "",
"EndpointID": "",
"Gateway": "",
"IPAddress": "",
"IPPrefixLen": 0,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "",
"DriverOpts": null
}
}
}
}
]
$ docker attach hostB
ieng@b78f6d49437c:~$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
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
14: eth1@if15: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:c0:a8:3a:02 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet 192.168.58.2/24 brd 192.168.58.255 scope global eth1
valid_lft forever preferred_lft forever
16: eth2@if17: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:c0:a8:3b:02 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet 192.168.59.3/24 brd 192.168.59.255 scope global eth2
valid_lft forever preferred_lft forever
18: eth0@if19: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:c0:a8:38:03 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet 192.168.56.3/24 brd 192.168.56.255 scope global eth0
valid_lft forever preferred_lft forever
ieng@b78f6d49437c:~$ read escape sequence
$ docker network disconnect nw59 hostB
$ docker inspect hostB | grep Networks -A 100
"Networks": {
"nw56": {
"IPAMConfig": {
"IPv4Address": "192.168.56.3"
},
"Links": null,
"Aliases": [
"b78f6d49437c"
],
"NetworkID": "6361b594a881ead174967e117fe821ddfc9c6085946282b46fa45b789da48b15",
"EndpointID": "11fa755819a59d75f30a0e14dc837aed6d4c073b659f457c335de00f2a7c25b4",
"Gateway": "192.168.56.1",
"IPAddress": "192.168.56.3",
"IPPrefixLen": 24,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "02:42:c0:a8:38:03",
"DriverOpts": null
},
"nw58": {
"IPAMConfig": {
"IPv4Address": "192.168.58.2"
},
"Links": null,
"Aliases": [
"b78f6d49437c"
],
"NetworkID": "d9e438cba1b35a0d37cd167fa572a4bf8bbf896592fcff7e52c843c55ef18316",
"EndpointID": "ad97fc0248583ba0c027cd04d202db5f5dd6c5b53d3229acfab1327f03819cc1",
"Gateway": "192.168.58.1",
"IPAddress": "192.168.58.2",
"IPPrefixLen": 24,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "02:42:c0:a8:3a:02",
"DriverOpts": null
}
}
}
}
]
$ docker attach hostB
ieng@b78f6d49437c:~$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
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
14: eth1@if15: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:c0:a8:3a:02 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet 192.168.58.2/24 brd 192.168.58.255 scope global eth1
valid_lft forever preferred_lft forever
18: eth0@if19: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:c0:a8:38:03 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet 192.168.56.3/24 brd 192.168.56.255 scope global eth0
valid_lft forever preferred_lft forever
Therefore, we got to know an ip address (192.168.59.3) and a network interface name (eth2) of hostB’s nw59.
