On Mon, Feb 15, 2010 at 02:33:05PM -0600, Boyd Stephen Smith Jr. wrote: > On Monday 15 February 2010 13:30:19 Freeman wrote: > > On Mon, Feb 15, 2010 at 12:59:33PM -0600, Boyd Stephen Smith Jr. wrote: > > > > > > Mixed systems that are supported with no configuration change: > > > stable/backports > > > unstable/experimental > > > > > > Mixed systems that need Default-Release set properly: > > > stable/testing > > > testing/unstable > > > testing/unstable/experimental > > > > > > Any other mixing will need a preferences file. > > > > Thanks Boyd. That is an interesting implementation chart. > > It's a side-effect of the priorities that are applied before you touch your > /etc/apt/preferences file. Default-Release pins something to 990. Backports > and experimental are tagged specially in either their Release or Packages > file > so they are pinned to priority 1. > > Technically, stable/testing/experimental, stable/unstable, > stable/unstable/experimental, and stable/experimental could also be run with > just Default-Release set and testing/experimental can be run with no > configuration. I don't recommend any of these for any reason -- there would > be too many dependency issues. > > > My system = Section 2, Item 3, if I stay away from stable/backports. > > > > Except for package rollbacks! Could a rollback to a version no longer > > included in any release represent a deviation from > > First, package downgrades aren't supported. Just a warning in general. The > old package can't be modified to "understand" any of the changes to your > system that the new package made. > > IME, this hasn't been a problem. Still, a purge/reinstall cycle is usually > safer than a downgrade, but even that may not work with every package. (In > particular, I don't believe DMBSes in Debian remove the data files when > purged.) >
Right. This would be an immediate rollback to the next-most recent archived version of the apt-cacher proxy in the case that I allow an intolerably buggy package. Some packages could fail to downgrade. Backups will be available. > > testing/unstable/experimental ? > > Yes. If you file a bug that "touches" one of the package versions no longer > in any Release file, it is very likely the first thing you'll be asked to do > is upgrade to the current testing/unstable/experimental. > . . . > > > However, could a rollback represent an incursion on the priority system? > > With testing/unstable/experimental, you'll have your Default-Release set to > testing so that package versions in testing get priority 990, package > versions > in unstable get priority 500, and package versions in experimental get > priority 1. > > 0. If there is a versioned dependency apt-get / aptitude will satisfy it; it > will not take into consideration versions that do not satisfy the dependency. > > 1. If the version you have installed is less than the version in testing apt- > get / aptitude will want to upgrade it to the testing version. > > 2. If the version you have installed is greater than the version in testing, > but less than the version in unstable, apt-get / aptitude will want to > upgrade > it to the unstable version. > > 3. If the version you have installed is greater than the version in unstable, > apt-get / aptitude will not want to upgrade it. > > You can use individual package pins to alter this. Pinning your currently > installed version to (501-)990 would prevent 2 above, but not 1. Pinning > your > currently installed version to 991(-999) would prevent both 1 and 2 above. > Pinning your currently installed version to 1 would cause 3 above to upgrade > your package to experimental instead. > I decided on a preferences file for caution and for future developments. Thus far: |Package: * |Pin: release a=testing |Pin-Priority: 990 |Package: * |Pin: release a=unstable |Pin-Priority: 700 |Package: * |Pin: release a=experimental |Pin-Priority: 500 |Package: * |Pin: release a=lenny/volatile |Pin-Priority: 300 |Package: * |Pin: release a=stable |Pin-Priority: 100 To rollback a package to a previous version existing only in my apt-cacher archive: |Package: < package_name > |Pin: version < nnn* > |Pin-Priority: 1001 (Interesting that preferences is too finicky of a file to include that as comments.) lenny/volatile is for freshclam. A standard update with aptitude before and after didn't show any changes. It would be interesting to see how aptitude's resolution suggestions are affected. -- Kind Regards, Freeman -- 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/20100216011026.ga4...@europa.office
