apt-get update The following signatures couldn't be verified because the public key is not available: NO_PUBKEY AA8E81B4331F7F50 NO_PUBKEY 112695A0E562B32A code example

Example 1: ubuntu 18.04 jenkins The following signatures couldn't be verified because the public key is not available:

Utils:

https://www.digitalocean.com/community/tutorials/how-to-install-jenkins-on-ubuntu-18-04

https://pkg.jenkins.io/debian-stable/

Solve the problem by adding this:
wget -q -O - https://pkg.jenkins.io/debian-stable/jenkins.io.key | sudo apt-key add -

Example 2: he following signatures couldn't be verified because the public key is not available: NO_PUBKEY 363A96A5CEA9EA27

sudo apt-key adv --keyserver ha.pool.sks-keyservers.net --recv-keys 363A96A5CEA9EA27