本文是 此长文中的部分内容，方便初学者照着操作。
问题说明
环境中部署了私有 Gitlab，一开始为了测试方便设置为公开仓库，后来为了安全，改成了私有仓库，此时再次运行流水线报拉取错误。
Running on ruoyi-gateway-28-5bgb1-l7z8q-845lt in /home/jenkins/agent/workspace/ruoyi-gateway
[Pipeline] {
[Pipeline] stage
[Pipeline] { (拉取代码)
[Pipeline] git
The recommended git tool is: NONE
using credential b4aa2f30-e922-423d-9ede-eccf6dc75a6d
Cloning the remote Git repository
Cloning repository https://gitlab.halfcoffee.com/root/ruoyi.git
> git init /home/jenkins/agent/workspace/ruoyi-gateway # timeout=10
Fetching upstream changes from https://gitlab.halfcoffee.com/root/ruoyi.git
> git --version # timeout=10
> git --version # 'git version 2.39.2'
using GIT_SSH to set credentials Git
Verifying host key using known hosts file
You're using 'Known hosts file' strategy to verify ssh host keys, but your known_hosts file does not exist, please go to 'Manage Jenkins' -> 'Security' -> 'Git Host Key Verification Configuration' and configure host key verification.
> git fetch --tags --force --progress -- https://gitlab.halfcoffee.com/root/ruoyi.git +refs/heads/*:refs/remotes/origin/* # timeout=10
ERROR: Error cloning remote repo 'origin'
hudson.plugins.git.GitException: Command "git fetch --tags --force --progress -- https://gitlab.halfcoffee.com/root/ruoyi.git +refs/heads/*:refs/remotes/origin/*" returned status code 128:
stdout:
stderr: remote: HTTP Basic: Access denied. The provided password or token is incorrect or your account has 2FA enabled and you must use a personal access token instead of a password. See https://gitlab.halfcoffee.com/help/topics/git/troubleshooting_git#error-on-git-fetch-http-basic-access-denied
fatal: Authentication failed for 'https://gitlab.halfcoffee.com/root/ruoyi.git/'
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandIn(CliGitAPIImpl.java:2842)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandWithCredentials(CliGitAPIImpl.java:2185)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl$1.execute(CliGitAPIImpl.java:635)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl$2.execute(CliGitAPIImpl.java:871)
at org.jenkinsci.plugins.gitclient.RemoteGitImpl$CommandInvocationHandler$GitCommandMasterToSlaveCallable.call(RemoteGitImpl.java:170)
at org.jenkinsci.plugins.gitclient.RemoteGitImpl$CommandInvocationHandler$GitCommandMasterToSlaveCallable.call(RemoteGitImpl.java:161)
at hudson.remoting.UserRequest.perform(UserRequest.java:211)
at hudson.remoting.UserRequest.perform(UserRequest.java:54)
at hudson.remoting.Request$2.run(Request.java:377)
at hudson.remoting.InterceptingExecutorService.lambda$wrap$0(InterceptingExecutorService.java:78)
at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at hudson.remoting.Engine$1.lambda$newThread$0(Engine.java:137)
at java.base/java.lang.Thread.run(Unknown Source)解决办法
一开始仓库公开时使用 https 地址进行拉取，设置为私有仓库后，可以通过 SSH 来免密进行拉取，具体操作如下：
创建 SSH 密钥对
使用 Linux 生成了一个 ssh 密钥对，公钥添加到 gitlab，私钥放在 jenkins 中。
在 Jenkins 中创建 git 秘钥
在 https://jenkins.halfcoffee.com/manage/credentials/store/system/domain/_/ 下创建一个 SSH 用户名和私钥。此秘钥用于通过 SSH 拉取代码，记录 ID：
同时在全局安全配置中建议进行下列配置，允许 ssh 连接时信任首次使用的公钥：
在 Gitlab 中创建 SSH 密钥
在用户的设置中添加“SSH密钥”，输入SSH公钥：
Jenkins 流水线配置
在 Gitlab 中获取仓库的 SSH 地址：
在 Jenkins 流水线中设置 Git 信息：
stage('拉取代码') {
git credentialsId: 'b4aa2f30-e922-423d-9ede-eccf6dc75a6d', url: 'ssh://git@gitlab.halfcoffee.com:10022/root/ruoyi.git'
container('maven') {
stage('代码编译') {
sh 'mvn -U clean install -Dmaven.test.skip=true && GIT_COMMIT=`git log --abbrev-commit --pretty=format:"%h" -1` && echo "GIT_COMMIT=$GIT_COMMIT" >> /home/jenkins/agent/env.txt'
}
}
}其中 git crendentialsId 为之前在 Jenkins 中创建的 SSH 私钥 ID；
URL 为 Gitlab 参考的 SSH 地址。
最终流水线的日志：
Running on ruoyi-gateway-31-jmcsl-csxd3-r6ztz in /home/jenkins/agent/workspace/ruoyi-gateway
[Pipeline] {
[Pipeline] stage
[Pipeline] { (拉取代码)
[Pipeline] git
The recommended git tool is: NONE
# 使用 ssh 秘钥拉取
using credential b4aa2f30-e922-423d-9ede-eccf6dc75a6d
Cloning the remote Git repository
Cloning repository ssh://git@gitlab.halfcoffee.com:10022/root/ruoyi.git
> git init /home/jenkins/agent/workspace/ruoyi-gateway # timeout=10
Fetching upstream changes from ssh://git@gitlab.halfcoffee.com:10022/root/ruoyi.git
> git --version # timeout=10
> git --version # 'git version 2.39.2'
using GIT_SSH to set credentials Git
# 此处发现访问的地址不在 known hosts 列表中，自动信任
Verifying host key using known hosts file, will automatically accept unseen keys
> git fetch --tags --force --progress -- ssh://git@gitlab.halfcoffee.com:10022/root/ruoyi.git +refs/heads/*:refs/remotes/origin/* # timeout=10
Avoid second fetch
Checking out Revision 7930d922da0de217ad196ba54849c6fd5540945a (origin/master)
> git config remote.origin.url ssh://git@gitlab.halfcoffee.com:10022/root/ruoyi.git # timeout=10
> git config --add remote.origin.fetch +refs/heads/*:refs/remotes/origin/* # timeout=10
> git rev-parse remotes/origin/master^{commit} # timeout=10
> git branch -a -v --no-abbrev --contains 7930d922da0de217ad196ba54849c6fd5540945a # timeout=10
> git config core.sparsecheckout # timeout=10
> git checkout -f 7930d922da0de217ad196ba54849c6fd5540945a # timeout=10
> git branch -a -v --no-abbrev # timeout=10
> git checkout -b master 7930d922da0de217ad196ba54849c6fd5540945a # timeout=10
Commit message: "test5"
First time build. Skipping changelog.