Hello, I built a system based on centos 5.3, now i'm planing to move to 5.4. To do it I rebuilt all rpms making some changes. When I use a common centos 5.3, it automatically detects that 5.4 is available and move update for it when i run yum update. How does this work? How the system detects new version and update for it? I thought centos-release rpm just update repo for it, but I saw this is not the case. Could someone gimme some light? Thanks -- Renato Botelho
Renato Botelho wrote:> Hello, > > I built a system based on centos 5.3, now i'm planing to move to 5.4. > To do it I rebuilt all rpms making some changes. > > When I use a common centos 5.3, it automatically detects that 5.4 > is available and move update for it when i run yum update. How > does this work? How the system detects new version and update > for it? > > I thought centos-release rpm just update repo for it, but I saw this > is not the case. > > Could someone gimme some light? >5.3 + updates = 5.4 There are usually no major problems in upgrading between point releases, but it is always a good idea to read the release notes. http://wiki.centos.org/Manuals/ReleaseNotes/CentOS5.4 -- Bowie
John R Pierce wrote:> Renato Botelho wrote: > >> My question is not *how* to update, but how the rpm detects a >> new version is available and automatically update to rpms from >> 5.4 version. >> >> > > I believe it gets the updates from /5/ on the yum repos, not /5.x/ > so when /5/ has rolled to be a link to /5.4/ instead of /5.3/, voila, > its getting the components from there. >Exactly. The "5.3" and "5.4" versions are a just collection of updates. When the updates that make up 5.4 are pushed out to the repos, you get updated to 5.4 on your next "yum update". -- Bowie
On Tue, Jan 19, 2010 at 3:30 PM, Bowie Bailey <Bowie_Bailey at buc.com> wrote:> John R Pierce wrote: >> Renato Botelho wrote: >> >>> My question is not *how* to update, but how the rpm detects a >>> new version is available and automatically update to rpms from >>> 5.4 version. >>> >>> >> >> I believe it gets the updates from /5/ ?on the yum repos, not /5.x/ >> so when /5/ has rolled to be a link to /5.4/ instead of /5.3/, voila, >> its getting the components from there. >> > > Exactly. ?The "5.3" and "5.4" versions are a just collection of > updates. ?When the updates that make up 5.4 are pushed out to the repos, > you get updated to 5.4 on your next "yum update". > > -- > BowieTo be more precise, any particular OS version (5.3, 5.4, etc...) is a collection of packages. Each package has its own version number that is totally separate from the "OS" version. All of the package version information is stored in the RPM database, and the "yum" tool looks at this database and compares package versions to those on the centos.org servers. If it finds packages that need updating, yum lists them as having an update available. An OS version is a snapshot of package versions that someone (redhat) has decided to stick a version number onto. So centos 5.3 is just as list of packages at a certain version. However, as soon as it is released, any package might have an update to it. OS versions tend to have updates that make some bigger changes to the system, as opposed to typical updates that are mainly security fixes. The centos servers manage the OS versions by making a link from 5 -> 5.4, for example. The files in /etc/yum.repos.d define how yum finds the servers and updates.