Yum 在 RHEL 7 上崩溃了； “[Errno 12] 超时...”存储库

Question

问题和症状：

[root@XXX ~]# yum install python-pip
Loaded plugins: enabled_repos_upload, langpacks, package_upload, product-id, search-disabled-repos, subscription-manager

epel/x86_64/metalink                                                                                                                |  16 kB  00:00:00
epel                                                                                                                                | 5.3 kB  00:00:00
https://XXX/pulp/repos/BMO_Org_01/Library/content/dist/rhel/server/7/7Server/x86_64/extras/os/repodata/repomd.xml: [Errno 12] Timeout on https://XXX/pulp/repos/BMO_Org_01/Library/content/dist/rhel/server/7/7Server/x86_64/extras/os/repodata/repomd.xml: (28, 'Operation timed out after 30001 milliseconds with 0 out of 0 bytes received')
Trying other mirror.
https://XXX/pulp/repos/BMO_Org_01/Library/content/dist/rhel/server/7/7Server/x86_64/extras/os/repodata/repomd.xml: [Errno 12] Timeout on https://XXX/pulp/repos/BMO_Org_01/Library/content/dist/rhel/server/7/7Server/x86_64/extras/os/repodata/repomd.xml: (28, 'Operation timed out after 30001 milliseconds with 0 out of 0 bytes received')
Trying other mirror.
https://XXX/pulp/repos/BMO_Org_01/Library/content/dist/rhel/server/7/7Server/x86_64/extras/os/repodata/repomd.xml: [Errno 12] Timeout on https://XXX/pulp/repos/BMO_Org_01/Library/content/dist/rhel/server/7/7Server/x86_64/extras/os/repodata/repomd.xml: (28, 'Operation timed out after 30001 milliseconds with 0 out of 0 bytes received')
Trying other mirror.

我已在上面的输出中将我的机器名称替换为“XXX”。

当尝试其他存储库时，这将继续并输出类似的日志。

我的机器似乎可以通过代理访问互联网：

[root@TBRISCCLPRAPP05 ~]# nslookup google.com
Server:         10.254.90.97
Address:        10.254.90.97#53

Non-authoritative answer:
Name:   google.com
Address: 172.217.164.206
Name:   google.com
Address: 2607:f8b0:400b:80f::200e

我已经导出了适当的 HTTP_PROXY 和 HTTPS_PROXY 环境变量。

机器信息：

NAME="Red Hat Enterprise Linux Server"
VERSION="7.7 (Maipo)"
ID="rhel"
ID_LIKE="fedora"