Ubuntu 22.04系统git/repo/github/codeup等 无法用ssh方式下载代码问题修复_ubuntu22.04 git clone ssh失败

在新安装的Ubuntu 22.04系统上，默认无法使用git下载代码，以及基于git的各种命令和服务，如repo、codeup、github等。执行命令，错误提示：

Permission denied (publickey).
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.
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或者

kex_exchange_identification: Connection closed by remote host
Connection closed by 123.123.123.123 port 22
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.
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首先确认本地和服务器端的sshkey设置都没有问题。

经调查，在openssh（8.x版本）由于安全原因，替换了默认的加密算法rsa，改为SHA-1。可以通过配置文件修改默认的加密算法，继续使用rsa算法。

查看本机安装的openssh-server版本，是8.9版本。

$ apt search openssh-server
Sorting... Done
Full Text Search... Done
openssh-server/jammy-updates,now 1:8.9p1-3ubuntu0.1 amd64 [installed]
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修改默认的加密算法，可在配置文件中添加如下选项：

PubkeyAcceptedKeyTypes +ssh-rsa
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修改本地的配置文件（~/.ssh/config）：

$ cat .ssh/config 
Host your.git.domain
HostName your.git.domain
# PreferredAuthentications publickey
PubkeyAcceptedKeyTypes +ssh-rsa
IdentityFile ~/.ssh/id_rsa
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修改后进行测试：
git服务器可正常访问。

$ ssh -p <git_port> git_user_name@your.git.domain
  ****    Welcome to Gerrit Code Review    ****
  Hi git_user_name, you have successfully connected over SSH.
Connection to gerrit.qisi.ltd closed.
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