docke網路型別詳解
阿新 • • 發佈:2021-11-30
一、bridge網路
1.建立一個測試容器
[root@localhost ~]# docker run -d -it --name busybox_1 busybox /bin/sh -c "while true;do sleep 3600;done" 03b308c847edd23f21ba69afb825d92f7aaeb05b1ff4431dd47ccee439a0361a
2.檢視當前機器docker有哪些網路
[root@localhost ~]# docker network ls NETWORK ID NAME DRIVER SCOPE fa30a4d17b5b bridge bridge local a03aaca35833 host host local d85c50eb947c none null local
3.檢視bridge詳細資訊(如果沒有指定網路,預設使用bridge網路)
[root@localhost ~]# docker network inspect fa30a4d17b5b #fa30a4d17b5b 為bridge的ID ..... "Containers": { #該欄位表示名稱為busybox_1的Container網路連線到的是bridge這個網路 "03b308c847edd23f21ba69afb825d92f7aaeb05b1ff4431dd47ccee439a0361a": { #容器的ID "Name": "busybox_1", #容器的名稱 "EndpointID": "c850f22941894ef8655a80a96e4be4c5045699b70b4bc17201f80f07a27a3b4d", "MacAddress": "02:42:ac:11:00:02", "IPv4Address": "172.17.0.2/16", #地址 "IPv6Address": "" } }, ......
4.檢視宿主機及容器busybox_1這個容器的網路介面,其中宿主機的veth66a7ab0@if110與容器中的eth0@if111網路介面實際上是一對pari,而veth66a7ab0@if110又連線到docker0上
[root@localhost ~]# ip a #檢視宿主網路介面 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 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 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 link/ether 52:54:00:fd:34:4b brd ff:ff:ff:ff:ff:ff inet 172.16.150.135/24 brd 172.16.150.255 scope global eth0 valid_lft forever preferred_lft forever 3: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default link/ether 02:42:23:c0:91:f9 brd ff:ff:ff:ff:ff:ff inet 172.17.0.1/16 scope global docker0 valid_lft forever preferred_lft forever 111: veth66a7ab0@if110: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master docker0 state UP group default link/ether 7e:59:81:8b:54:a2 brd ff:ff:ff:ff:ff:ff link-netnsid 0 [root@localhost ~]# docker exec busybox_1 ip a #檢視busybox_1容器的網路介面 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue qlen 1000 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 110: eth0@if111: <BROADCAST,MULTICAST,UP,LOWER_UP,M-DOWN> mtu 1500 qdisc noqueue link/ether 02:42:ac:11:00:02 brd ff:ff:ff:ff:ff:ff inet 172.17.0.2/16 scope global eth0 valid_lft forever preferred_lft forever inet6 fe80::42:acff:fe11:2/64 scope link valid_lft forever preferred_lft forever
5.驗證veth66a7ab0網路與docker0相連線
[root@localhost ~]# brctl show #如果沒有該命令,yum安裝 bridge-utils軟體包即可 bridge name bridge id STP enabled interfaces docker0 8000.024223c091f9 no veth66a7ab0
6.建立第二測試容器
[root@localhost ~]# docker run -d -it --name busybox_2 busybox /bin/sh -c "while true;do sleep 3600;done" b884db0bf4a862281b1dfb66457c7f565896fce1a40151619e80c2c5b1499216
7.再次檢視bridge網路資訊
[root@localhost ~]# docker network inspect bridge...... "Containers": { "03b308c847edd23f21ba69afb825d92f7aaeb05b1ff4431dd47ccee439a0361a": { "Name": "busybox_1", "EndpointID": "c850f22941894ef8655a80a96e4be4c5045699b70b4bc17201f80f07a27a3b4d", "MacAddress": "02:42:ac:11:00:02", "IPv4Address": "172.17.0.2/16", "IPv6Address": "" }, "b884db0bf4a862281b1dfb66457c7f565896fce1a40151619e80c2c5b1499216": { "Name": "busybox_2", #busybox_2 也連線到bridge "EndpointID": "a5e56917165daf2965bf7f24cf9ce58c88e4ff3c1118544c49ca5f25172af28d", "MacAddress": "02:42:ac:11:00:03", "IPv4Address": "172.17.0.3/16", "IPv6Address": "" } }, ......
8.檢視本地網路介面,發現多了113: vethc039e93@if112
[root@localhost ~]# ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 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 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 link/ether 52:54:00:fd:34:4b brd ff:ff:ff:ff:ff:ff inet 172.16.150.135/24 brd 172.16.150.255 scope global eth0 valid_lft forever preferred_lft forever 3: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default link/ether 02:42:23:c0:91:f9 brd ff:ff:ff:ff:ff:ff inet 172.17.0.1/16 scope global docker0 valid_lft forever preferred_lft forever 111: veth66a7ab0@if110: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master docker0 state UP group default link/ether 7e:59:81:8b:54:a2 brd ff:ff:ff:ff:ff:ff link-netnsid 0 113: vethc039e93@if112: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master docker0 state UP group default link/ether ea:a2:a8:dc:48:78 brd ff:ff:ff:ff:ff:ff link-netnsid 1
9.檢視bridge網路資訊,發現docker0連線率兩個介面了
[root@localhost ~]# brctl show bridge name bridge id STP enabled interfaces docker0 8000.024223c091f9 no veth66a7ab0 vethc039e93
簡單拓撲圖:
總結:實質上docker容器之間通過與docker0介面連線.實現先互直接通訊,感覺有點像交換機?
10.docker訪問公網簡單拓撲圖
小結:實質上docker訪問公網網路通過docker0 NAT轉發實現
二、host網路
1.檢視當前服務埠
[root@localhost ~]# netstat -tnlp #除了sshd,沒有其他服務埠 Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 965/sshd tcp6 0 0 :::22 :::* LISTEN 965/sshd
2.建立一個測試容器,指定使用host網路
[root@localhost ~]# docker run -d --privileged --name my_centos --network host docker.io/centos /usr/sbin/init #建議使用centos映象,後續測試需要 cfb8d105dcb44947ce794d890b67c905df9aa1ba67ef2675fd1a51177d47835d
3.檢視host網路資訊(注意容器的網路資訊)
[root@localhost ~]# docker network inspect host ...... "Containers": { "cfb8d105dcb44947ce794d890b67c905df9aa1ba67ef2675fd1a51177d47835d": { "Name": "my_centos", "EndpointID": "4250d74b28f8125688bd7d0f1475a7d107135c0e87367a9c35c197fd981b7cd4", "MacAddress": "", #可以看到我們建立的容器此時並沒有Mac和IP地址 "IPv4Address": "", "IPv6Address": "" } ......
4.進入容器內部,檢視網路資訊
[root@localhost ~]# docker exec -it my_centos /bin/bash [root@localhost /]# ip a #預設沒有相關檢視命令 bash: ip: command not found [root@localhost /]# ifconfig bash: ifconfig: command not found [root@localhost /]# yum install net-tools -y #我們yum安裝(是不是很奇怪,沒有網路地址怎麼安裝) [root@localhost /]# ifconfig #內容太多不粘了,但是顯示的應該是當前宿主機的網路資訊 [root@localhost /]# netstat -tnlp Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN - tcp6 0 0 :::22 :::* LISTEN -
5.在容器總安裝httpd伺服器,並啟動
[root@localhost /]# yum install httpd -y [root@localhost /]# systemctl restart httpd [root@localhost /]# netstat -tnlp #發現多了80埠 Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 1305/httpd tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN - tcp6 0 0 :::22 :::* LISTEN -
6.退出容器,在宿主機上檢視當前網路連線
[root@localhost ~]# netstat -tnlp #宿主機上80埠也被開放了 Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 7032/httpd tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 965/sshd tcp6 0 0 :::22 :::* LISTEN 965/sshd
7.對於host模式的思考:
host模式下是怎麼佔領埠的?
host模式端口占用模式是你的容器佔用你主機上當前所監聽的埠(官網描述為publish),比如我們都知道Nginx佔用80埠,那麼當我們用host模式啟動的時候,主機上的80埠會被Nginx佔用,這個時候其他的容器就不能指定我們的8080埠了,但是可以指定其他埠,所以說一臺主機上可以執行多個host模式的容器,只要彼此監聽的埠不一樣就行。
host模式下使用-p或者-P會出現WARNING: Published ports are discarded when using host network mode
當你是host模式的時候,主機會自動把他上面的埠分配給容器,這個時候使用-p或者-P是無用的。但是還是可以在Dockerfile中宣告EXPOSE埠
host模式設計的原因
host模式設計出來就是為了效能,訪問主機的埠就能訪問到我們的容器,使容器直接暴露在公網下,但是這卻對docker的隔離性造成了破壞,使得安全性大大降低。這種模式有利有弊,對於每個人來說看法都不一樣,具體取捨看個人。
三、none網路
1.建立一個測試容器
[root@localhost ~]# docker run -d --name test1 --network none busybox /bin/sh -c "while true;do sleep 36000;done" ca1771ebfe436137156568cd570c116d12bd85e782dbec365c9f62a70209d028
2.檢視none網路資訊
[root@localhost ~]# docker network inspect none ...... "Containers": { "ca1771ebfe436137156568cd570c116d12bd85e782dbec365c9f62a70209d028": { "Name": "test1", #容器無法看到Mac和IP地址 "EndpointID": "ddcff44cdedb78f59108c6978345a256baa8bb09965461b2ffac58d5334fdba6", "MacAddress": "", "IPv4Address": "", "IPv6Address": "" } ......
3.進入容器檢視網路資訊
[root@localhost ~]# docker exec -it test1 /bin/sh / # ip a #只有迴環介面 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue qlen 1000 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
小結:none
網路的容器只有一個自己的迴環介面,沒有任何 IP 地址分配,所有這個網路中的每個容器都是孤立的。但是所有網路配置我們都可以自己配置,如IP、網絡卡等