6.7. Upgrade dari Satu Distribusi Stable ke Berikutnya

Salah satu fitur yang paling terkenal adalah kemampuannya untuk mengupgrade sistem terinstall dari satu rilis stable ke rilis berikutnya: dist-upgrade — istilah yang mashur — besar kontribusinya terhadap reputasi rroyek. Dengan sedikit tindakan pencegahan, mengupgrade sebuah komputer dapat membutuhkan waktu beberapa menit, atau belasan menit, tergantung kecepatan unduh dari repositori paket.

6.7.1. Prosedur yang Direkomendasikan

Karena Debian memiliki beberapa waktu untuk evolusi antara rilis stable, Anda harus membaca catatan rilis sebelum melakukan upgrade.

KEMBALI KE DASAR Catatan rilis

Catatan rilis untuk sebuah sistem operasi (dan, lebih umum, untuk perangkat lunak) adalah sebuah dokumen yang memberikan gambaran perangkat lunak, dengan beberapa rincian mengenai fakta suatu versi. Dokumen ini biasanya berupa perbandingan singkat ke dokumentasi lengkapnya, dan mereka biasanya terdapat daftar fitur yang telah diperkenalkan sejak versi sebelumnya. Mereka juga memberikan rincian tentang prosedur upgrade, peringatan untuk penggunan versi sebelumnya, dan terkadang berupa ralat.

Release notes are available online: the release notes for the current stable release have a dedicated URL, while older release notes can be found with their codenames:

→ https://www.debian.org/releases/stable/releasenotes

→ https://www.debian.org/releases/buster/releasenotes

In this section, we will focus on upgrading a Buster system to Bullseye. This is a major operation on a system; as such, it is never 100% risk-free, and should not be attempted before all important data has been backed up.

Kebiasaan baik lainnya yang membuat upgrade lebih mudah (dan ringkas) adalah membereskan paket terinstall dan tersisa hanya yang diperlukan saja. Peralatan yang membantu untuk melakukan hal tersebua termasuk aptitude, deborphan dan debfoster (lihat Bagian 6.2.7, “Pelacakan Otomatis Paket Terinstall”). Misalnya, Anda dapat menggunakan perintah berikut, kemudian menggunakan mode interaktif aptitude untuk pemeriksaan ulang dan jadwal penghapusan yang rapih:

# deborphan | xargs aptitude --schedule-only remove

Now for the upgrading itself. First, you need to change the /etc/apt/sources.list file to tell APT to get its packages from Bullseye instead of Buster. If the file only contains references to Stable rather than explicit codenames, the change isn't even required, since Stable always refers to the latest released version of Debian. In both cases, the database of available packages must be refreshed (with the apt update command or the refresh button in synaptic).

Ketika sumber paket baru ini telah terdaftar, Anda harus melakukan upgrade minimal terlebih dahulu dengan apt upgrade. Dengan melakukan upgrade dalam dua langkah, kita dapat memermudah pekerjaan peralatan manajer paket dan seringkali untuk memastikan bahwa kita memiliki versi terbarunya, yang mungkin memiliki kumpulan perbaikan kutu dan diperlukan perbaikan untuk melengkapi upgrade distribusi lengkap.

Once this first upgrade is done, it is time to handle the upgrade itself, either with apt full-upgrade, aptitude, or synaptic. You should carefully check the suggested actions before applying them: you might want to add suggested packages or deselect packages which are only recommended and known not to be useful. In any case, the front-end should come up with a scenario ending in a coherent and up-to-date Bullseye system. Then, all you need is to do is wait while the required packages are downloaded, answer the debconf questions and possibly those about locally modified configuration files, and sit back while APT does its magic.

6.7.2. Menangani Masalah setelah Pembaharuan

Dalam kegemasan usaha terbaik maintainer Debian, upgrade sistem utama tidak selalu selancar yang Anda inginkan. Versi terbaru perangkat lunak mungkin tidak cocok dengan versi sebelumnya (misalnya, perilaku bawaannya atau format data mereka mungkin berubah). Juga, beberapa kutu mungkin terselip oleh crack walaupun fase testing yang selalu mendahului rilis Debian.

Untuk mengantisipasi beberapa masalah ini, Anda dapat menginstall paket apt-listchanges, yang menampilkan informasi tentang kemungkinan masalah di permulaan upgrade paket. Informasi ini dikompilasi oleh maintainer paket Debian dan dimasukkan dalam berkas /usr/share/doc/paket/NEWS.Debian untuk memberi manfaat bagi pengguna. Membaca berkas perubahan ini (melalui apt-listchanges) akan membantu Anda menghindari kejutan buruk.

You might sometimes find that the new version of a software doesn't work at all. This generally happens if the application isn't particularly popular and hasn't been tested enough; a last-minute update can also introduce regressions which are only found after the stable release. In both cases, the first thing to do is to have a look at the bug tracking system at https://bugs.debian.org/package, and check whether the problem has already been reported. If this is case, it will be also listed before the upgrade begins, if you have apt-listbugs installed. If it hasn't, you should report it yourself with reportbug. If it is already known, the bug report and the associated messages are usually an excellent source of information related to the bug:

terkadang sebuah patch telah ada, dan tersedia pada laporan kutu; Anda dapat mengompilasi ulang versi tetap paket yang rusak di lokal (lihat Bagian 15.1, “Membangun ulang sebuah Paket dari Source-nya”);
dalam kasus lain, pengguna mungkin menemukan solusi masalah tersebut dan dibagi dalam penjelasannya dalam balasan ke laporan tersebut;
dan dalam kasus lain, paket perbaikkan mungkin telah dipersiapkan dan tersedia secara publik oleh maintainer.

Depending on the severity of the bug, a new version of the package may be prepared specifically for a new revision of the stable release. When this happens, the fixed package is made available in the proposed-updates section of the Debian mirrors (see Bagian 6.1.2.3, “Pengajuan Pembaharuan”). The corresponding entry can then be temporarily added to the sources.list file, and updated packages can be installed with apt or aptitude.

Sometimes the fixed package isn't available in this section yet because it is pending a validation by the Stable Release Managers. You can verify if that is the case on their web page. Packages listed there aren't available yet, but at least you know that the publication process is ongoing.

→ https://release.debian.org/proposed-updates/stable.html

6.7.3. Cleaning Up after an Upgrade

APT usually ensures a clean upgrade, pulling in new and updated dependencies, or removing conflicting packages. But even being such a great tool, it cannot cover all tasks users and administrators will face after an upgrade, because they require a human decision.

6.7.3.1. Paket-paket yang dihapus dari Arsip Debian

Sometimes the Debian ftpmasters remove packages from the Debian archive, because they contain release critical bugs, were abandoned by their upstream author or their package maintainer, or simply reached their end of life. In this case a newer Debian release does not ship the package anymore. To find all packages, which do not have a package source, use the apt-show-versions command:

$ apt-show-versions | grep "No available version"

A similar result can be achieved by aptitude search ~o. If the packages found are not required anymore, they should be purged from the system, because they will not face any updates for critical or security related bugs anymore.

6.7.3.2. Paket-paket Transisi dan Dummy

Sometimes, it might be necessary for a package to get a new name. In this case often the old package is kept as an (almost) empty package, depending on the new one and installing only the mandatory files in /usr/share/doc/package/. Such packages are called "dummy" or "transitional" packages. If the package maintainer in charge also changed the section of this package to oldlibs, then tools like aptitude, deboprhan, or debfoster (see sidebar ALTERNATIVE deborphan dan debfoster) can pickup these packages to suggest their removal.

Unfortunately there is currently no foolproof way of making sure that these packages are automatically removed or picked by the tools mentioned above. One way to check if the system still has some of these packages installed, is to look through the package descriptions of installed packages and then check the results. Be careful not to schedule the results for automatic removal, because this method can lead to false positives:

$ dpkg -l | grep ^ii | grep -i -E "(transition|dummy)"

Because the new package is pulled in as a dependency of the transitional package, it is usually marked as automatically installed and might be scheduled for removal if you try to purge the transitional package from your system. In this case you can use either of the approaches described in sidebar TIP Penghapusan dan instalasi pada saat yang sama and Bagian 6.2.7, “Pelacakan Otomatis Paket Terinstall” to selectively remove the transitional package.

6.7.3.3. Berkas-berkas Konfigurasi Tak Terpakai atau Lama

If the upgrade was successful there might be some configuration file cruft, either from dpkg (see Bagian 5.2.3, “Checksums, Daftar Berkas Konfigurasi”), ucf or from removed packages. The latter can be purged by using apt autoremove --purge. The configuration files that were handled by dpkg or ucf during the upgrade process have left some counterparts with a dedicated suffix (e.g. .dpkg-dist, .dpkg-old, .ucf-old). Using the find or locate command can help to track them down. If they are no longer of any use, they can be deleted.

6.7.3.4. Berkas yang tak dimiliki oleh sebarang Paket

The Debian policy enforces that packages don't leave files behind when they are purged. Violating this principle is a serious bug and you will rarely encounter it. If you do, report it; and if you are curious though, you can use the cruft or cruft-ng package to check your system for files not owned by any package.