enter code here
aptly mirror create -architectures=amd64 -with-sources=true -with-udebs=true focal-main http://us.archive.ubuntu.com/ubuntu/ focal main Downloading http://us.archive.ubuntu.com/ubuntu/dists/focal/InRelease... Success downloading http://us.archive.ubuntu.com/ubuntu/dists/focal/InRelease gpgv: Signature made Thu 23 Apr 2020 01:34:17 PM EDT using RSA key ID C0B21F32 gpgv: [don't know]: invalid packet (ctb=00) gpgv: keydb_search failed: invalid packet gpgv: Can't check signature: public key not found gpgv: Signature made Thu 23 Apr 2020 01:34:17 PM EDT using RSA key ID 991BC93C gpgv: [don't know]: invalid packet (ctb=00) gpgv: keydb_search failed: invalid packet gpgv: Can't check signature: public key not found
Looks like some keys are missing in your trusted keyring, you may consider importing them from keyserver:
gpg --no-default-keyring --keyring trustedkeys.gpg --keyserver keyserver.ubuntu.com --recv-keys 3B4FE6ACC0B21F32 871920D1991BC93C
Sometimes keys are stored in repository root in file named Release.key, to import such key:
wget -O - https://some.repo/repository/Release.key | gpg --no-default-keyring --keyring trustedkeys.gpg --import
Looks like some keys are missing in your trusted keyring, you may consider importing them from keyserver:
gpg --no-default-keyring --keyring trustedkeys.gpg --keyserver keyserver.ubuntu.com --recv-keys 3B4FE6ACC0B21F32 871920D1991BC93C
Sometimes keys are stored in repository root in file named Release.key, to import such key:
wget -O - https://some.repo/repository/Release.key | gpg --no-default-keyring --keyring trustedkeys.gpg --import
ERROR: unable to fetch mirror: verification of detached signature failed: exit status 2