前言

由于眾所周知的原因，在國內拉取國外的docker鏡像時，速度會很慢，甚至失敗。比如拉取dotnet core的鏡像。

比如以下兩個鏡像，拉取的時候非常慢

mcr.microsoft.com/dotnet/core/runtime:3.1-buster-slim
mcr.microsoft.com/dotnet/core/sdk:3.1-buster

既然是網絡原因，那么就可以通過以下兩種方式解決

1.國內鏡像倉庫

2.從國外鏡像倉庫下載鏡像上傳到國內鏡像倉庫

配置國內鏡像倉庫

倉庫列表

可自行搜索關鍵字docker國內鏡像源尋找

配置方法

在CentOS中可以通過修改daemon配置文件/etc/docker/daemon.json來配置

sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
{
  "registry-mirrors": ["鏡像倉庫"]
}
EOF
sudo systemctl daemon-reload
sudo systemctl restart docker

從國外鏡像倉庫下載鏡像上傳到國內鏡像倉庫

前提

有一臺訪問主流鏡像倉庫速度快的境外服務器，安裝好docker

開通阿里云的容器鏡像倉庫服務

步驟

1.使用docker pull命令下載鏡像

[root@104 ~]# docker pull mcr.microsoft.com/dotnet/core/sdk:3.1-buster
3.1-buster: Pulling from dotnet/core/sdk
d6ff36c9ec48: Pull complete 
c958d65b3090: Pull complete 
edaf0a6b092f: Pull complete 
80931cf68816: Pull complete 
7b9b87089c2a: Pull complete 
4f2c2524f197: Pull complete 
b7b0f8dc0c5c: Pull complete 
Digest: sha256:1aa53e4fa32dbba836e64e7863955b6b2b165f3a4f8f8aeed648a249300fae07
Status: Downloaded newer image for mcr.microsoft.com/dotnet/core/sdk:3.1-buster
mcr.microsoft.com/dotnet/core/sdk:3.1-buster

2.查看鏡像信息，并且tag到阿里云鏡像倉庫

[root@104 ~]# docker images
REPOSITORY                          TAG                 IMAGE ID            CREATED             SIZE
mcr.microsoft.com/dotnet/core/sdk   3.1-buster          9ab567a29502        2 weeks ago         708MB

[root@104 ~]# docker tag 9ab567a29502 registry.cn-shenzhen.aliyuncs.com/dotnetcore-vincent/sdk:3.1-buster

如上命令，使用tag命令把鏡像關聯到鏡像倉庫，用到的參數是image id和倉庫地址，然后push

[root@104 ~]# docker push registry.cn-shenzhen.aliyuncs.com/dotnetcore-vincent/sdk:3.1-buster
The push refers to repository [registry.cn-shenzhen.aliyuncs.com/dotnetcore-vincent/sdk]
f506d7422ef0: Layer already exists 
5188b84c74d0: Layer already exists 
896ff95e1760: Layer already exists 
e5df62d9b33a: Layer already exists 
7a9460d53218: Layer already exists 
b2765ac0333a: Layer already exists 
0ced13fcf944: Layer already exists 
3.1-buster: digest: sha256:1aa53e4fa32dbba836e64e7863955b6b2b165f3a4f8f8aeed648a249300fae07 size: 1800

因為我的鏡像倉庫里已經有了這個鏡像，所以不會再次上傳

使用

把鏡像上傳好之后，就可以在Dockerfile中使用了，速度超快，如下面的Dockerfile

#See https://aka.ms/containerfastmode to understand how Visual Studio uses this Dockerfile to build your images for faster debugging.
FROM registry.cn-shenzhen.aliyuncs.com/dotnetcore-vincent/aspnet:3.1-buster-slim AS base
WORKDIR /app
EXPOSE 80
EXPOSE 443
FROM registry.cn-shenzhen.aliyuncs.com/dotnetcore-vincent/sdk:3.1-buster AS build
WORKDIR /src
COPY ["DockerDemo/DockerDemo.csproj", "DockerDemo/"]
RUN dotnet restore "DockerDemo/DockerDemo.csproj"
COPY . .
WORKDIR "/src/DockerDemo"
RUN dotnet build "DockerDemo.csproj" -c Release -o /app/build
FROM build AS publish
RUN dotnet publish "DockerDemo.csproj" -c Release -o /app/publish
FROM base AS final
WORKDIR /app
COPY --from=publish /app/publish .
ENTRYPOINT ["dotnet", "DockerDemo.dll"]

最后

給出兩個dotnet core相關的鏡像地址

registry.cn-shenzhen.aliyuncs.com/dotnetcore-vincent/sdk:3.1-buster
registry.cn-shenzhen.aliyuncs.com/dotnetcore-vincent/aspnet:3.1-buster-slim
registry.cn-shenzhen.aliyuncs.com/rabbitmq-vincent/rabbitmq:3.8.8
registry.cn-shenzhen.aliyuncs.com/dotnet-vincent/sdk:5.0 
registry.cn-shenzhen.aliyuncs.com/dotnet-vincent/aspnet:5.0

以上就是關于“Docker加速鏡像”的介紹，大家如果想了解更多相關知識，不妨來關注一下動力節點的Docker菜鳥教程，里面的內容豐富，由淺到深，適合沒有基礎的朋友學習，相信對大家會有所幫助的。