Hello folks! At the recent Ubuntu Engineering Sprint, we planned to move forward with installing "chrony" by default in all Ubuntu 25.10+ images, replacing systemd-timesyncd. Chrony is already in "main", is being used by some official Ubuntu cloud-images, and was enabled to utilize "Network Time Security" (NTS) in Ubuntu Plucky Puffin 25.04.
NTS uses the port 4460/TCP for its NTS KeyExchange, in addition to the normal port 123/UDP for NTP, to allow for authenticated time synchronization. Time is a critical factor in cryptography and needs to be trusted, e.g. when checking certificate validity or when enabling DNSSEC. NTS in chrony can already be tested today in Ubuntu 25.04+ by running: $ apt-mark auto systemd-timesyncd && apt install chrony It can be rolled back in the same way: $ apt-mark auto chrony && apt install systemd-timesyncd Installing chrony from the "ubuntu-minimal" seed will drop "systemd-timesyncd" from the default installation, but bring in an additional dependency on "libedit2" and in total grow the image size by 803 kB. After installation, "chrony" can manually be switched to another "time-daemon" as described above. I intend to move forward with transitioning to "chrony" in the week starting June 2. My plan and proposed seed changes are described in [LP] and I updated the Ubuntu Questing Quokka [25.10] release schedule accordingly. Cheers, -- Lukas [LP] https://bugs.launchpad.net/ubuntu/+bug/2111342 [25.10] https://discourse.ubuntu.com/t/questing-quokka-release-schedule/36462 -- Ubuntu-release mailing list Ubuntu-release@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-release
