尝试使用以下方法更新：
sudo apt-get update
收到以下回复：
Ign:1 http://dl.google.com/linux/chrome/deb stable InRelease
Hit:2 http://dl.google.com/linux/chrome/deb stable Release
Get:3 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB]
Hit:5 http://in.archive.ubuntu.com/ubuntu bionic InRelease
Hit:6 http://ppa.launchpad.net/umang/indicator-stickynotes/ubuntu bionic InRelease
Hit:7 http://in.archive.ubuntu.com/ubuntu bionic-updates InRelease
Get:8 http://in.archive.ubuntu.com/ubuntu bionic-backports InRelease [74.6 kB]
Get:9 https://deb.torproject.org/torproject.org bionic InRelease [4,244 B]
Err:9 https://deb.torproject.org/torproject.org bionic InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 74A941BA219EC810
Reading package lists... Done
W: GPG error: https://deb.torproject.org/torproject.org bionic InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 74A941BA219EC810
E: The repository 'https://deb.torproject.org/torproject.org bionic InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
然后我尝试：
~$ sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 74A941BA219EC810
并得到
Executing: /tmp/apt-key-gpghome.LvVh1YzHpU/gpg.1.sh --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 74A941BA219EC810
^[[A^[[Bgpg: packet(13) too large
gpg: read_block: read error: Invalid packet
gpg: no valid OpenPGP data found.
gpg: Total number processed: 0
我错过了什么？
答案1
由于某些原因，密钥服务器似乎比预期花费的时间更长，至少对我来说是这样。您可以尝试使用以下方法导入 tor 密钥：
curl https://deb.torproject.org/torproject.org/A3C4F0F979CAA22CDBA8F512EE8CBC9E886DDD89.asc | gpg --import
gpg --export A3C4F0F979CAA22CDBA8F512EE8CBC9E886DDD89 | apt-key add -