Installation problems - Public key not available

[user111]

Dear community,

I´m trying to install the ELK Stack as explained in the official documentation here:

Install Elasticsearch with Debian Package | Elasticsearch Guide [8.1] | Elastic

I´m running a Ubuntu 18.04 machine and I´m getting the following error while executing sudo apt-get update && sudo apt-get install elasticsearch

Error:

Error:5 https://artifacts.elastic.co/packages/8.x/apt stable InRelease
  The following signatures could not be verified because their public key is not available: NO_PUBKEY D27D666CD88E42B4
Reading package lists... Done
W: GPG error: https://artifacts.elastic.co/packages/8.x/apt stable InRelease: The following signatures could not be verified because their public key is not available: NO_PUBKEY D27D666CD88E42B4
E: The repository https://artifacts.elastic.co/packages/8.x/apt stable InRelease is unsigned.
N: Updating from such a repository cannot be performed in a secure manner, so it is disabled by default.
N: See the apt-secure(8) man page for more details on creating repository packages and customizing them.

Can someone please assist me here. I did the installation as explained step by step.

Thanks in advance.

[spinscale (Alexander Reelsen)]

The above linked documentation has a paragraph named Import the Elasticsearch PGP Key at Install Elasticsearch with Debian Package | Elasticsearch Guide [8.1] | Elastic

Have you done this?

[user111]

Hi Spinscale,

yes, I´ve done every single step. This is why I`m really confused.
Thanks for your fast reply.

If I check the available keys I can find it in the apt-key list:

pub   rsa2048 2013-09-16 [SC]
      4609 5ACC 8548 582C 1A26  99A9 D27D 666C D88E 42B4
uid        [ unkown] Elasticsearch (Elasticsearch Signing Key) <dev_ops@elasticsearch.org>
sub   rsa2048 2013-09-16 [E]

/etc/apt/trusted.gpg.d/ansible_ubuntu_ansible.gpg