root@xzlhost:~# apt-get update
Err:1 https://node.histb.com:9088/update/repo/armhf histb InRelease
Temporary failure resolving 'node.histb.com'
Err:2 http://repo.huaweicloud.com/ubuntu-ports focal InRelease
Temporary failure resolving 'repo.huaweicloud.com'
Err:3 https://mirrors.ustc.edu.cn/docker-ce/linux/ubuntu focal InRelease
Temporary failure resolving 'mirrors.ustc.edu.cn'
Err:4 http://repo.huaweicloud.com/ubuntu-ports focal-updates InRelease
Temporary failure resolving 'repo.huaweicloud.com'
Err:5 http://repo.huaweicloud.com/ubuntu-ports focal-backports InRelease
Temporary failure resolving 'repo.huaweicloud.com'
Err:6 http://repo.huaweicloud.com/ubuntu-ports focal-security InRelease
Temporary failure resolving 'repo.huaweicloud.com'
Reading package lists... Done
W: Failed to fetch http://repo.huaweicloud.com/ubuntu-ports/dists/focal/InRelease Temporary failure resolving 'repo.huaweicloud.com'
W: Failed to fetch http://repo.huaweicloud.com/ubuntu-ports/dists/focal-updates/InRelease Temporary failure resolving 'repo.huaweicloud.com'
W: Failed to fetch http://repo.huaweicloud.com/ubuntu-ports/dists/focal-backports/InRelease Temporary failure resolving 'repo.huaweicloud.com'
W: Failed to fetch http://repo.huaweicloud.com/ubuntu-ports/dists/focal-security/InRelease Temporary failure resolving 'repo.huaweicloud.com'
W: Failed to fetch https://mirrors.ustc.edu.cn/docker-ce/linux/ubuntu/dists/focal/InRelease Temporary failure resolving 'mirrors.ustc.edu.cn'
W: Failed to fetch https://node.histb.com:9088/update/repo/armhf/dists/histb/InRelease Temporary failure resolving 'node.histb.com'
W: Some index files failed to download. They have been ignored, or old ones used instead.
