Createrepo causes module conflict on RHEL 8 reposync

Solution Verified - Updated

Environment

  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • createrepo_c version 0.16.2-1.el8[Fixed]

Issue

  • How to manually insert module metadata into existing repodata

  • Repository mirror for RHEL8 created via createrepo_c command does not handle modules information correctly:

    # yum update
...
Error:
 Problem 1: cannot install both perl-libs-4:5.24.4-404.module+el8.1.0+2926+ce7246ad.x86_64 and perl-libs-4:5.26.3-416.el8.x86_64
  - package perl-Algorithm-Diff-1.1903-10.module+el8.1.0+2926+ce7246ad.noarch requires perl(:MODULE_COMPAT_5.24.4), but none of the providers can be installed
  - cannot install the best update candidate for package perl-libs-4:5.26.3-416.el8.x86_64
  - cannot install the best update candidate for package perl-Algorithm-Diff-1.1903-9.el8.noarch

  • After switching to direct update from Red Hat provided repositories, then there are no errors.

Resolution

RHEL 8

 # reposync --download-metadata --repo <repo-id>
  • If you use createrepo on a RHEL 8 repository, you must also:
    • add the comps.xml with createrepo for groups
    • add the updateinfo.xml from cache for security package identification
    • add the modules.yaml from cache for modules, and you have to do this or you will encounter massive dependency issues.
# rm -rf /var/cache/dnf
# yum module list && yum updateinfo
# reposync --repo <repo-id> --download-path=/var/www/html

### With the repository downloaded, we now need to build the repodata. We should be sitting in the root of the repository.

# cd /var/www/html/<repo-id>

# cp $(find /var/cache/dnf/<repo-id>* -name *comps.xml) comps.xml
# createrepo -g comps.xml ./

### Find and add the module data  **NOTE** createrepo_c-0.16.2-2.el8 and later will automatically detect and include the modules.yaml, if present in the repo directory.

#  gunzip $(find /var/cache/dnf/<repo-id>* -name *modules.yaml.gz) -c > modules.yaml
# modifyrepo modules.yaml repodata/

###Find and add the security data
# gunzip $(find /var/cache/dnf/<repo-id>* -name *updateinfo.xml.gz) -c > updateinfo.xml
# modifyrepo updateinfo.xml repodata/

Note

  • The modular metadata will be all inclusive. If you use this on minimal repositories, it won't know what packages are missing

RHEL 9

  • RHEL 9 is not affected by this issue.
    • RHEL 9 shipped package createrepo_c-0.17.2-5.el9.x86_64.rpm is higher than the fix version createrepo_c-0.16.2-2.el8.

Root Cause

  • Red Hat Enterprise Linux 8 introduced new feature - modules. Information on this feature can be found in official documentation : Introduction to modules

  • Unfortunately the RPM packages do not contain data that are required for separating packages into modules. As reposync and createrepo_c(versions prior to createrepo_c-0.16.2-1.el8) only process RPM package information, they cannot handle the modules and so module information does not exist in the created repo. As a result yum/dnf is having 2 conflicting packages with the same version.

  • The issue was tracked in Red Hat Bugzilla This content is not included.Bug 1795936 - [RFE] createrepo_c should be able to handle modules information and is fixed in version createrepo_c-0.16.2-2.el8

Diagnostic Steps

  • Any version lower than createrepo_c-0.16.2-1.el8 would face this issue.

  • Check the installed version of package

    # rpm -q createrepo_c 
createrepo_c-0.11.0-3.el8.x86_64
SBR
Product(s)

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