在ubuntu中使用conda创建虚拟环境，报网络错误

请问下面这个问题怎么解决？
起因：使用xshell中的ssh方式连接服务器，想创建一个虚拟环境conda create -n ddnm python=3.8，服务器用的校园网连接（学校的服务器只能用内网连接）
报错如下：
CondaHTTPError: HTTP 000 CONNECTION FAILED for url mirrors.tuna.tsinghua.edu.cn/anacon...
Elapsed: -

An HTTP error occurred when trying to retrieve this URL.
HTTP errors are often intermittent, and a simple retry will get you on your way.
‘http//mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main/linux-64’
已经尝试的解决方法：
1.vim ~/.condarc增删过镜像，删过defaults,改过ssl_verify
2.可以ping通百度IP地址，ping百度域名不行不认识域名
3.使用sudo su获取管理员权限建虚拟环境conda create -n ddnm python=3.8
，报错如下CondaHTTPError: HTTP 000 CONNECTION FAILED for url repo.anaconda.com/pkgs/main/linux-...
Elapsed: -

An HTTP error occurred when trying to retrieve this URL.
HTTP errors are often intermittent, and a simple retry will get you on your way.

If your current network has www.anaconda.com blocked, please file
a support request with your network engineering team.

ConnectionError(MaxRetryError(“HTTPSConnectionPool(host=’repo.anaconda.com’, port=443): Max retries exceeded with url: /pkgs/main/linux-32/repodata.json.bz2 (Caused by NewConnectionError(‘<urllib3.connection.VerifiedHTTPSConnection object at 0xf577506c>: Failed to establish a new connection: [Errno -3] Temporary failure in name resolution’))”))
：