On Feb 4, 2014, at 12:25 AM, PaulNM <deb...@paulscrap.com> wrote: > On 02/04/2014 01:53 AM, Rick Thomas wrote: >> >> On Feb 3, 2014, at 8:37 PM, Scott Ferguson >> <scott.ferguson.debian.u...@gmail.com> wrote: >> >>> Mirrors were updating a couple of days ago.... and if you tried to use >>> one during the updating period you would get errors. Could be the problem. >> >> What would it take to make a mirror update atomically? For example, >> download all the updates, get everything staged and ready to go but not yet >> visible to http clients, then at the flip of a switch, have all the updates >> become visible at once, perhaps with some kind of a "callback" to the >> currently active clients to tell them that things have changed and they >> should re-get everything. Maybe LVM snapshots would be helpful here? > > It wouldn't take anything, if the mirror is following the directions on > http://www.debian.org/mirror/ftpmirror > > Specifically "MUST perform a 2-stage sync" which is to avoid this very > problem. "Rationale: if archive mirroring is done in a single stage, > there will be periods of time during which the index files will > reference files not yet mirrored."
Ahhh... That's good. I didn't know that. Which just goes to show the relevance of the maxim: "Read the documentation before you try to 'fix' it!" > >> >> It would require some re-thinking of the protocol used by apt-get/aptitude >> -- to be sure the stuff you just downloaded is still current and hasn't been >> changed by an update while you were downloading... and minimize wasted >> effort by recognizing an update as early as possible. >> > > I politely disagree on this point, this is something well outside of a > package manager's jurisdiction. It's up to the mirror to say what's > available. > > Another thing to look at is if there are any proxy/caching servers > involved that may be serving old versions of the indexes. Indeed. It's the presence of proxy/cacheing servers (specifically, http.debian.net) that prompted this discussion in the first place. So let me re-phrase the question: What would it take to make the apt-get protocol robust in the face of updates in combination with proxy and/or caching servers? >> Just a thought... >> >> Rick >> > > Its a good thought, that's why the maintainers ask mirrors do this this > way. :) Thanks for correcting my misunderstandings! (-: Still thinking... Rick -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/77cd6716-bad3-4aff-bfaf-4ee9064d3...@pobox.com
