Hello,
to make the client working with RHEL 9.4 kernel is sufficient to comment or remove:
#ifndef KERNEL_HAS_IOV_ITER_IOVEC
#error iov_iter_iovec() is a required feature
#endif
from /opt/beegfs/src/client/client_module_7/source/os/iov_iter.h
and then execute
/etc/init.d/beegfs-client rebuild
Paolo Oliveri