Sns test problems

hi there, I git clone the sns-testing repo to my local environment and run it step by step.
When I run
mkdir -p “$(dirname “${DX_NET_JSON}”)”
cp “$DX_NET_JSON” “${DX_NET_JSON}.tmp” 2>/dev/null # save original config if present
echo ‘{
“local”: {
“bind”: “”,
“type”: “ephemeral”,
“replica”: {
“subnet_type”: “system”,
“port”: 8000
}’ > “${DX_NET_JSON}”
sudo ./bin/dfx start --clean;
mv “${DX_NET_JSON}.tmp” “$DX_NET_JSON” 2>/dev/null # restore original config if it was present
it can work, and print:

then I follow the next instruction, open another command line, and input “bash”, it downloads a lot of wasm files, but failed on “dfx nns import”:

So, did I make a wrong step anywhere?

I tried to upgrade my dfx version(current 0.13.1), and it prints:

network problem?

Hi again, I have changed my hosts configuration, then install dfx 0.14.3, and all steps work!