> Try running: > sudo apt-get update # one more time, to be sure > # then > apt-cache policy ntp > > and see what version it refers to.
Thanks for the suggestions folks but there's not much to see there, no packages are pinned. I've made some progress, though. A closer look at the output reveals that "Packages" is "Ign:", which is apparently [1] apt-get's way of saying "I was unable to download it but that's not a problem". # apt-get update Ign:1 http://mymirror/debian stretch InRelease [...] Get:3 http://mymirror/debian stretch Release [118 kB] Get:4 http://mymirror/debian stretch Release.gpg [2434 B] Ign:5 http://mymirror/debian stretch/main amd64 Packages [...] strace tells me that apt-get uses the cached version in /var/lib/apt/lists/, which may be why it thinks that not being able to download it is not a problem. Unfortunately, the Packages file in /var/lib/apt/lists/ is out of date by months because it pertains to 9.2 while the mirror has 9.4. Diffing the two shows why apt-get looks for the wrong version of ntp : Package: ntp -Version: 1:4.2.8p10+dfsg-3+deb9u1 +Version: 1:4.2.8p10+dfsg-3+deb9u2 Installed-Size: 1804 What I'd like to know now is : what prevents apt-get from downloading the Packages file from the mirror ? Wget can ! [1] https://superuser.com/questions/454867/