I run 4 small exits, 4 guard and 6 bridge relays on various versions of Ubuntu. These are difficult to upgrade as I get message similar to: “Release file for https://deb.torproject.org/torproject.org/dists/focal/InRelease is expired”. I’ve installed necessary prerequisites including apt-transport-https, tor.sources file, gpg key and deb.torproject.org-keyring . Restarting tor is same obsolete version. I find several versions of install/upgrade to tor on the website that are at odds with each other (outdated). Can someone point me to the fully correct upgrade path? I most recently used: Why and how I can enable Tor Package Repository in Debian? | Tor Project | Support
This error message signals that this repository is serving an outdated version of index. Debian repositories (used by debian derivatives including Ubuntu) may include a Valid-Until date-time so updating from this repository is forbidden after this date-time. This is a security measure that helps with detecting replay attacks (an attacker can serves an outdated copy of repository to victims, so victims installs a software with certain vulnerabilities and allows for furthur exploitation), but it also makes installing from repository not receiving updates impossible (unless otherwise configured).
See Check-Valid-Until in sources.list(5) manpage.
The problematic file mentioned has Valid-Until: Sat, 20 Dec 2025 23:24:04 UTC set so updating softwares from it in 2026 is blocked by apt’s security measure.
Based on the reported last modified date seen here, my guess is Tor’s support for Ubuntu 20.04 LTS (Focal Fossa) has already ended, due to this OS version reaching EOL in April 2025, thus is not safe to use anymore.
You may proceed to:
- upgrade your server to a newer LTS version (22.04 Jammy Jellyfish or 24.04 Noble Numbat, I recommend upgrading to 24.04 because then you can keep using 24.04 until 2029. Note you need to first upgrade to 22.04 before upgrading to 24.04. " You can only upgrade from one LTS release directly to the next sequential LTS release", said here)
- modify your apt sources.list entry to reflect your new Ubuntu version
- retry upgrade Tor softwares.