My board has Ubuntu Linux 16.04.6, and I am trying to install google chrome by using the process described here.
Two first steps are going smoothly:
1) wget -q -O - https://dl.google.com/linux/linux_signing_key.pub | sudo apt-key add -
2) echo "deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main" | sudo tee /etc/apt/sources.list.d/google-chrome.list
However the third step gets many failures
3) sudo apt-get update
root@localhost:~# apt-get update
Err:1 http://ports.ubuntu.com/ubuntu-ports xenial InRelease
Temporary failure resolving 'ports.ubuntu.com'
Err:2 http://dl.google.com/linux/chrome/deb stable InRelease
Temporary failure resolving 'dl.google.com'
Err:3 http://ports.ubuntu.com/ubuntu-ports xenial-updates InRelease
Temporary failure resolving 'ports.ubuntu.com'
Err:4 http://ports.ubuntu.com/ubuntu-ports xenial-backports InRelease
Temporary failure resolving 'ports.ubuntu.com'
Err:5 http://mirrors.ustc.edu.cn/ubuntu-ports xenial InRelease
Temporary failure resolving 'mirrors.ustc.edu.cn'
Err:6 http://ports.ubuntu.com/ubuntu-ports xenial-security InRelease
Temporary failure resolving 'ports.ubuntu.com'
Err:7 http://mirrors.ustc.edu.cn/ubuntu-ports xenial-backports InRelease
Temporary failure resolving 'mirrors.ustc.edu.cn'
Err:8 http://mirrors.ustc.edu.cn/ubuntu-ports xenial-proposed InRelease
Temporary failure resolving 'mirrors.ustc.edu.cn'
Err:9 http://mirrors.ustc.edu.cn/ubuntu-ports xenial-security InRelease
Temporary failure resolving 'mirrors.ustc.edu.cn'
Err:10 http://mirrors.ustc.edu.cn/ubuntu-ports xenial-updates InRelease
Temporary failure resolving 'mirrors.ustc.edu.cn'
Reading package lists... Done
W: Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/xenial/InRelease Temporary failure resolving 'ports.ubuntu.com'
W: Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/xenial-updates/InRelease Temporary failure resolving 'ports.ubuntu.com'
W: Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/xenial-backports/InRelease Temporary failure resolving 'ports.ubuntu.com'
W: Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/xenial-security/InRelease Temporary failure resolving 'ports.ubuntu.com'
W: Failed to fetch http://mirrors.ustc.edu.cn/ubuntu-ports/dists/xenial/InRelease Temporary failure resolving 'mirrors.ustc.edu.cn'
W: Failed to fetch http://mirrors.ustc.edu.cn/ubuntu-ports/dists/xenial-backports/InRelease Temporary failure resolving 'mirrors.ustc.edu.cn'
W: Failed to fetch http://mirrors.ustc.edu.cn/ubuntu-ports/dists/xenial-proposed/InRelease Temporary failure resolving 'mirrors.ustc.edu.cn'
W: Failed to fetch http://mirrors.ustc.edu.cn/ubuntu-ports/dists/xenial-security/InRelease Temporary failure resolving 'mirrors.ustc.edu.cn'
W: Failed to fetch http://mirrors.ustc.edu.cn/ubuntu-ports/dists/xenial-updates/InRelease Temporary failure resolving 'mirrors.ustc.edu.cn'
W: Failed to fetch http://dl.google.com/linux/chrome/deb/dists/stable/InRelease Temporary failure resolving 'dl.google.com'
W: Some index files failed to download. They have been ignored, or old ones used instead.
[1]: https://www.itzgeek.com/how-tos/linux/ubuntu-how-tos/install-google-chrome-on-ubuntu-16-04.html
There are many responses to similar issues in the web that refer to dns problems (I tried almost all the proposed solutions/workarounds), but since ping to the domains that get temporary failures resolving ('ports.ubuntu.com', 'dl.google.com', 'mirrors.ustc.edu.cn',...) work properly, it does not seem that this is the right root cause.
root@localhost:~# ping ports.ubuntu.com
PING ports.ubuntu.com (91.189.88.150) 56(84) bytes of data.
64 bytes from astomi.canonical.com (91.189.88.150): icmp_seq=1 ttl=52 time=69.3 ms
64 bytes from astomi.canonical.com (91.189.88.150): icmp_seq=2 ttl=52 time=71.3 ms
64 bytes from astomi.canonical.com (91.189.88.150): icmp_seq=3 ttl=52 time=69.1 ms
Any help to investigate this problem is appreciated.