Ceph

Quoting from https://en.opensuse.org/openSUSE:Shared_library_packaging_policy

A versioned package is allowed to ship multiple library files,
provided they share the same numbers and these numbers always
change in lockstep throughout.

Relevant portion of the spec file showing that libceph-common.so.0 is owned by librados2 package:

%files -n librados2
%{_libdir}/librados.so.*
%dir %{_libdir}/ceph
%{_libdir}/ceph/libceph-common.so.*
%if %{with lttng}
%{_libdir}/librados_tp.so.*
%endif

Source of SO version number discrepancy:

librados2 SO is defined in src/librados/CMakeLists.txt:

  set_target_properties(librados PROPERTIES
    OUTPUT_NAME rados
    VERSION 2.0.0
    SOVERSION 2
    VISIBILITY_INLINES_HIDDEN ON) 

and libceph-common SO in src/CMakeLists.txt:

set_target_properties(ceph-common PROPERTIES
  SOVERSION 0
  SKIP_RPATH TRUE)