On Monday, December 29, 2025 10:22:13 AM Eastern Standard Time Iztok Gregori via ceph-users wrote: > On 29/12/25 14:57, Anthony D'Atri wrote: > > > > > > >> > >> > >> In my case it will be used to "adopt" the services, but after that what > >> is its intended usage? The "orchestrator" should be used to add/remove > >> new hosts and to upgrade the cluster. > > > > > Cephadm *is* the orchestrator. The nomenclature may seem misleading. > > There’s part that runs on each node as well as a Manager module, and CLI > > commands. > > Understand. My question was around the "cephadm" command, the one > documentation says that has to be installed on all the nodes to start > the "adoption" process. I'm not sure if this command is needed only for > that process or is an integral part of the cephadm/orchestrator.
The cephadm system is split into two parts - a manager module and the cephadm command. The command is often called "the binary" or a little more verbosely "the cephadm binary". A system may often have two or more copies of the cephadm binary on a node. There's the copy that is installed by an administrator (typically) that is run for bootstrapping or adoption and for some administrative commands. Then there's a copy that is pushed to nodes from the mgr module. This copy of the binary is coupled to the mgr module (you can find cached copies under /var/lib/ ceph). I hope this short architectural description is helpful. :-) > > > >> I'm asking this question because my upgrade path consists in multiple > >> consecutive upgrades and I see that for the latest version of Quincy > >> (17.2.9) and for newer Ceph releases there is no cephadm "package" for > >> el8 > > > > > Check the compatibility matrix in the docs. > > > Mhmm... I suspect that I'm entering in some edge case here (end exiting > the subject of this thread). I have a cluster running Ceph Octopus > 15.2.17 on EL8 (almost all the nodes, some nodes are EL7 but can be > reinstalled/removed). My goal is to upgrade it AND to embrace cephadm as > orchestrator. My plan is/was: > > 1. Adopt cephadm (with octopus containers) > 2. Upgrade to Quincy. > 3. Upgrade to Squid. > > But now looking to the various compatibility matrices I'm start to worry > that this is not possible: > > - Podman on EL8 is version 4, but from the table > https://docs.ceph.com/en/squid/cephadm/compatibility/#cephadm-compatibility-> > with-podman podman will not run with Octopus. > - There is no mention of EL8 in > https://docs.ceph.com/en/squid/start/os-recommendations/ > > I could skip the adoption with Octopus containers and go directly with > adoption+upgrade to Quincy. But I'll end up with in any case with most > hosts running EL8 which I cannot find in any matrices. > > So the best solution will be to upgrade all the machines to EL9 and > concurrently upgrade Ceph to Quincy. For the MON and MGR shouldn't be > too much of a problem (it should be possible to add a new monitor with > newer ceph release to an existing cluster), but how to reinstall the OSD > servers without data movement? > > In theory it should suffice to put the cluster in 'noout', reinstall the > host without touching the OSD disks and then recreate the OSDs. Is this > possible? > > Thank you for your time! > Iztok > > > > _______________________________________________ > ceph-users mailing list -- [email protected] > To unsubscribe send an email to [email protected] _______________________________________________ ceph-users mailing list -- [email protected] To unsubscribe send an email to [email protected]
