docker 网络访问诊断

本地docker开启nginx服务等，
发现linux系统重启之后，无法访问，
进入容器内部，发现可以访问
但是容器外部，映射端口无法访问；

诊断之前，发现docker0没有IP绑定

root@book:/etc/docker# ip addr
3: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group defaultlink/ether 02:42:1e:fd:2a:6a brd ff:ff:ff:ff:ff:ffinet6 fe80::42:1eff:fefd:2a6a/64 scope linkvalid_lft forever preferred_lft forever

诊断之后，docker0绑定了网络: 172.17.0.1/16

root@book:/etc/docker# ip addr
...
3: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group defaultlink/ether 02:42:1e:fd:2a:6a brd ff:ff:ff:ff:ff:ffinet 172.17.0.1/16 brd 172.17.255.255 scope global docker0valid_lft forever preferred_lft foreverinet6 fe80::42:1eff:fefd:2a6a/64 scope linkvalid_lft forever preferred_lft forever

诊断方法：重启docker服务

root@book:/etc/docker# service docker stop
root@book:/etc/docker# service docker start
root@book:/etc/docker# systemctl status docker.service
● docker.service - Docker Application Container EngineLoaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)Active: active (running) since Tue 2023-08-08 15:09:02 UTC; 3s ago
TriggeredBy: ● docker.socketDocs: https://docs.docker.comMain PID: 1454337 (dockerd)Tasks: 87Memory: 46.3MCPU: 3.739sCGroup: /system.slice/docker.service├─1454337 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock├─1454578 /usr/bin/docker-proxy -proto tcp -host-ip 0.0.0.0 -host-port 5000 -container-ip 172.17.0.2 -container-port 50>├─1454584 /usr/bin/docker-proxy -proto tcp -host-ip :: -host-port 5000 -container-ip 172.17.0.2 -container-port 5000├─1454627 /usr/bin/docker-proxy -proto tcp -host-ip 0.0.0.0 -host-port 28090 -container-ip 172.18.0.2 -container-port 8>├─1454635 /usr/bin/docker-proxy -proto tcp -host-ip 0.0.0.0 -host-port 8443 -container-ip 172.17.0.3 -container-port 443├─1454636 /usr/bin/docker-proxy -proto tcp -host-ip :: -host-port 28090 -container-ip 172.18.0.2 -container-port 8090├─1454653 /usr/bin/docker-proxy -proto tcp -host-ip :: -host-port 8443 -container-ip 172.17.0.3 -container-port 443├─1454693 /usr/bin/docker-proxy -proto tcp -host-ip 0.0.0.0 -host-port 8090 -container-ip 172.17.0.3 -container-port 80├─1454706 /usr/bin/docker-proxy -proto tcp -host-ip :: -host-port 8090 -container-ip 172.17.0.3 -container-port 80├─1454727 /usr/bin/docker-proxy -proto tcp -host-ip 0.0.0.0 -host-port 8022 -container-ip 172.17.0.3 -container-port 22└─1454732 /usr/bin/docker-proxy -proto tcp -host-ip :: -host-port 8022 -container-ip 172.17.0.3 -container-port 22...
root@book:/etc/docker# ping 172.17.0.2
PING 172.17.0.2 (172.17.0.2) 56(84) bytes of data.
64 bytes from 172.17.0.2: icmp_seq=1 ttl=64 time=12.7 ms
64 bytes from 172.17.0.2: icmp_seq=2 ttl=64 time=0.041 ms
64 bytes from 172.17.0.2: icmp_seq=3 ttl=64 time=0.054 ms
root@book:/etc/docker# curl -i localhost:5000
HTTP/1.1 200 OK
Cache-Control: no-cache
Date: Tue, 08 Aug 2023 15:10:01 GMT
Content-Length: 0