Armbian is not an operating system per se. It is a build framework which creates working Linux images by combining a customized Linux kernel for the specific board with a userspace flavor in either Debian or Ubuntu. The images we provide are in practical POV just a side product from testing the build framework and the actually supported images to a certain level and mostly there for user convenience. Due to limited resources Armbian can only support the most recent upstream LTS userspaces which at the moment are Debian 12 aka Bookworm and Ubuntu 22.04 aka Jammy. The upstream support for Debian Stretch has ended June 30, 2022. Technically the user space you are using is Debian Stretch.  Armbian provides the boot environment and linux kernel, the user space comes from either Debian or Ubuntu (depending on the version you choose to install). From the Debian release page: : " Debian 9.13 was released July 18th, 2020. Debian 9.0 was initially released on June 17th, 2017. The release included many major changes, described in our press release and the Release Notes. Debian 9 (stretch) has been superseded by Debian 10 (buster). Security updates have been discontinued as of July 6th, 2020." So Debian stretch stopped being supported over three years ago.  Armbian generally follows similar time lines to the underlying support of the Debian or Ubuntu user spaces.  The message you are getting is because Armbian recently cleaned up the support status of these older releases.  So even though no updates have been created for the Armbian parts for likely years, you didn't have any message that you weren't getting any updates until the recent change. I installed the newest bookworm image (Armbian_community_24.5.0-trunk.250_Rock64_bookworm_current_6.6.22_minimal.img.xz 😞 flashed it to SD card, booted... Rock64 boot was okay, via PuTTY it asked me to log in, but I have no PW, not any credentials, of course. Shouldn´t it ask me for a root PW first??? You can post now and register later. If you have an account, sign in now to post with your account.
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