[slurm-users] Exclude Slurm packages from the EPEL yum repository

Mon Jan 25 14:36:03 UTC 2021

On 1/25/21 2:59 PM, Andy Riebs wrote:
> Several things to keep in mind...
> 
>  1. Slurm, as a product undergoing frequent, incompatible revisions, is
>     not well-suited for provisioning from a stable public repository! On
>     the other hand, it's just not that hard to build a stable version
>     where you can directly control the upgrade timing.

I agree that Slurm is probably not well suited for a public repository 
because of the special care that *must* be taken when upgrading between 
major versions.

When I use both EPEL for a lot of nice software (Munge, Lmod, ...), AND I 
build my own Slurm RPMs, now suddenly slurm RPMs from EPEL upsets this 
stable scenario.

>  2. If you really want a closely managed source for your Slurm RPMs, get
>     them from the SchedMD website.

All of us get the Slurm source from the SchedMD website.  And all of us 
have to build our own RPMs from that source (a simple one-liner).  SchedMD 
doesn't provide any RPMs.

>  3. "You could have solicited advice..." -- while this is certainly true,
>     for many of us in the open source world, the standard is "release
>     something quickly, and then improve it, based in part on feedback,
>     over time."

I don't think this trial-and-error-like approach is suitable for Slurm. 
We're running production HPC clusters that need to stay very stable.

>  4. Slurm packages (and other contributions, including suggestions on this
>     mailing list) that haven't been provided by SchedMD have probably been
>     provisioned and tested by a volunteer -- be sure to keep the
>     conversation civil!

We all have to build our own Slurm RPMs, and we should not get them from a 
volunteer.  IMHO, building Slurm RPMs is very simple.  It's the deployment 
and upgrading which is the hard part of the equation.

I think my points quoted below deserve careful consideration by the EPEL 
volunteer, because the results could be potentially harmful.

Thanks,
Ole

> Andy Riebs
> 
> On 1/25/2021 2:47 AM, Ole Holm Nielsen wrote:
>> On 1/23/21 9:43 PM, Philip Kovacs wrote:
>>> I can assure you it was easier for you to filter slurm from your repos 
>>> than it was for me to make them available to both epel7 and epel8.
>>>
>>> No good deed goes unpunished I guess.
>>
>> I do sympathize with your desire to make the Slurm installation a bit 
>> easier by providing RPMs via the EPEL repo.  I do not underestimate the 
>> amount of work it takes to add software to EPEL.
>>
>> However, I have several issues with your approach:
>>
>> 1. Breaking existing Slurm installations could cause big time problems 
>> at a lot of sites!  The combined work to repair broken installations at 
>> many sites might be substantial.  Sites who are more than two releases 
>> behind 20.11 could end up with dysfunctional clusters.  You are 
>> undoubtedly aware that 20.11.3 fixes a major problem in 20.11.2 wrt. 
>> OpenMPI, so the upgrade from 20.02 to 20.11.2 may cause problems.
>>
>> 2. Your EPEL RPMs *must not* upgrade between major Slurm releases, like 
>> the 20.02 to 20.11 upgrade that almost happened at our site! I refer 
>> again to the delicate upgrade procedure described in 
>> https://wiki.fysik.dtu.dk/niflheim/Slurm_installation#upgrading-slurm
>>
>> 3. You could have solicited advice from the slurm-users list before 
>> planning your EPEL Slurm packages.
>>
>> 4. How do you plan to keep updating future Slurm minor versions on EPEL 
>> in a timely fashion?
>>
>> 5. How did you build your RPM packages?  The built-in options may be 
>> important, for example, this might be recommended:
>> $ rpmbuild -ta slurm-xxx.tar.bz2 --with mysql --with slurmrestd
>>
>> 6. Building Slurm RPM packages is actually a tiny part of what it takes 
>> to install Slurm from scratch.  There are quite a number of 
>> prerequisites and other things to set up besides the RPMs, see
>> https://wiki.fysik.dtu.dk/niflheim/Slurm_installation
>> plus configuration of Slurm itself and its database.
>>
>> In conclusion, I would urge you to ensure that your EPEL packages won't 
>> mess up existing Slurm installations!  I agree with Ryan Novosielski 
>> that you should rename your RPMs so that they don't overwrite packages 
>> built by SchedMD's rpmbuild system.
>>
>> I propose that you add the major version 20.11 right after the "slurm" 
>> name so that your EPEL RPMs would be named "slurm-20.11-*" like in:
>>
>> slurm-20.11-20.11.2-2.el7.x86_64
>>
>> People with more knowledge of RPM than I have could help you ensure that 
>> no unwarranted upgrades or double Slurm installations can take place.
>>
>> Thanks,
>> Ole
>>
>>
>>> On Saturday, January 23, 2021, 07:03:08 AM EST, Ole Holm Nielsen 
>>> <ole.h.nielsen at fysik.dtu.dk> wrote:
>>>
>>>
>>> We use the EPEL yum repository on our CentOS 7 nodes.  Today EPEL
>>> surprisingly delivers Slurm 20.11.2 RPMs, and the daily yum updates
>>> (luckily) fail with some errors:
>>>
>>> --> Running transaction check
>>> ---> Package slurm.x86_64 0:20.02.6-1.el7 will be updated
>>> --> Processing Dependency: slurm(x86-64) = 20.02.6-1.el7 for package:
>>> slurm-libpmi-20.02.6-1.el7.x86_64
>>> --> Processing Dependency: libslurmfull.so()(64bit) for package:
>>> slurm-libpmi-20.02.6-1.el7.x86_64
>>> ---> Package slurm.x86_64 0:20.11.2-2.el7 will be an update
>>> --> Processing Dependency: pmix for package: slurm-20.11.2-2.el7.x86_64
>>> --> Processing Dependency: libfreeipmi.so.17()(64bit) for package:
>>> slurm-20.11.2-2.el7.x86_64
>>> --> Processing Dependency: libipmimonitoring.so.6()(64bit) for package:
>>> slurm-20.11.2-2.el7.x86_64
>>> --> Processing Dependency: libslurmfull-20.11.2.so()(64bit) for package:
>>> slurm-20.11.2-2.el7.x86_64
>>> ---> Package slurm-contribs.x86_64 0:20.02.6-1.el7 will be updated
>>> ---> Package slurm-contribs.x86_64 0:20.11.2-2.el7 will be an update
>>> ---> Package slurm-devel.x86_64 0:20.02.6-1.el7 will be updated
>>> ---> Package slurm-devel.x86_64 0:20.11.2-2.el7 will be an update
>>> ---> Package slurm-perlapi.x86_64 0:20.02.6-1.el7 will be updated
>>> ---> Package slurm-perlapi.x86_64 0:20.11.2-2.el7 will be an update
>>> ---> Package slurm-slurmdbd.x86_64 0:20.02.6-1.el7 will be updated
>>> ---> Package slurm-slurmdbd.x86_64 0:20.11.2-2.el7 will be an update
>>> --> Running transaction check
>>> ---> Package freeipmi.x86_64 0:1.5.7-3.el7 will be installed
>>> ---> Package pmix.x86_64 0:1.1.3-1.el7 will be installed
>>> ---> Package slurm.x86_64 0:20.02.6-1.el7 will be updated
>>> --> Processing Dependency: slurm(x86-64) = 20.02.6-1.el7 for package:
>>> slurm-libpmi-20.02.6-1.el7.x86_64
>>> --> Processing Dependency: libslurmfull.so()(64bit) for package:
>>> slurm-libpmi-20.02.6-1.el7.x86_64
>>> ---> Package slurm-libs.x86_64 0:20.11.2-2.el7 will be installed
>>> --> Finished Dependency Resolution
>>> Error: Package: slurm-libpmi-20.02.6-1.el7.x86_64
>>> (@/slurm-libpmi-20.02.6-1.el7.x86_64)
>>>              Requires: libslurmfull.so()(64bit)
>>>              Removing: slurm-20.02.6-1.el7.x86_64
>>> (@/slurm-20.02.6-1.el7.x86_64)
>>>                  libslurmfull.so()(64bit)
>>>              Updated By: slurm-20.11.2-2.el7.x86_64 (epel)
>>>                  Not found
>>> Error: Package: slurm-libpmi-20.02.6-1.el7.x86_64
>>> (@/slurm-libpmi-20.02.6-1.el7.x86_64)
>>>              Requires: slurm(x86-64) = 20.02.6-1.el7
>>>              Removing: slurm-20.02.6-1.el7.x86_64
>>> (@/slurm-20.02.6-1.el7.x86_64)
>>>                  slurm(x86-64) = 20.02.6-1.el7
>>>              Updated By: slurm-20.11.2-2.el7.x86_64 (epel)
>>>                  slurm(x86-64) = 20.11.2-2.el7
>>>    You could try using --skip-broken to work around the problem
>>>    You could try running: rpm -Va --nofiles --nodigest
>>>
>>>
>>> We still run Slurm 20.02 and don't want EPEL to introduce any Slurm
>>> updates!!  Slurm must be upgraded with some care, see for example
>>> https://wiki.fysik.dtu.dk/niflheim/Slurm_installation#upgrading-slurm 
>>> <https://wiki.fysik.dtu.dk/niflheim/Slurm_installation#upgrading-slurm>
>>>
>>> Therefore we must disable EPEL's slurm RPMs permanently.  The fix is to
>>> add to the file /etc/yum.repos.d/epel.repo an "exclude=slurm*" line like
>>> the last line in:
>>>
>>> [epel]
>>> name=Extra Packages for Enterprise Linux 7 - $basearch
>>> #baseurl=http://download.fedoraproject.org/pub/epel/7/$basearch 
>>> <http://download.fedoraproject.org/pub/epel/7/$basearch>
>>> metalink=https://mirrors.fedoraproject.org/metalink?repo=epel-7&arch=$basearch&infra=$infra&content=$contentdir 
>>> <https://mirrors.fedoraproject.org/metalink?repo=epel-7&arch=$basearch&infra=$infra&content=$contentdir> 
>>>
>>> failovermethod=priority
>>> enabled=1
>>> gpgcheck=1
>>> gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7
>>> exclude=slurm*
>>>
>>> /Ole