scala – 无法在线安装sbt(以下官方指南)

echo "deb https://dl.bintray.com/sbt/debian /" | sudo tee -a /etc/apt/sources.list.d/sbt.list
sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 2EE0EA64E40A89B84B2DF73499E82A75642AC823
sudo apt-get update
sudo apt-get install sbt

我得到了什么：

fino@envy:bin$echo "deb https://dl.bintray.com/sbt/debian /" | sudo tee -a /etc/apt/sources.list.d/sbt.list
[sudo] password for fino: 
deb https://dl.bintray.com/sbt/debian /

fino@envy:bin$sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 2EE0EA64E40A89B84B2DF73499E82A75642AC823
Executing: /tmp/tmp.YqbI7qVhAP/gpg.1.sh --keyserver
hkp://keyserver.ubuntu.com:80
--recv
2EE0EA64E40A89B84B2DF73499E82A75642AC823
gpg: requesting key 642AC823 from hkp server keyserver.ubuntu.com

?: keyserver.ubuntu.com: Host not found
gpgkeys: HTTP fetch error 7: couldn't connect: Connection timed out
gpg: no valid OpenPGP data found.
gpg: Total number processed: 0
gpg: keyserver communications error: keyserver unreachable
gpg: keyserver communications error: public key not found
gpg: keyserver receive failed: public key not found

我试过直接连接到互联网或“导出all_proxy = sock5h：// ip：port”因为我在大陆:-)