PREIN

/bin/sh

getent group mapred >/dev/null || groupadd -r mapred
getent passwd mapred >/dev/null || /usr/sbin/useradd --comment "Apache Hadoop MapReduce" --shell /sbin/nologin -M -r -g mapred -G hadoop --home /var/cache/hadoop-mapreduce mapred

PREUN

/bin/sh

/usr/share/rpm-helper/del-service hadoop $1 hadoop-historyserver.service

POSTIN

/bin/sh

/usr/share/rpm-helper/add-service hadoop $1 hadoop-historyserver.service 

/usr/bin/systemd-tmpfiles --create /usr/lib/tmpfiles.d/hadoop-mapreduce.conf

POSTUN

/bin/sh

/usr/share/rpm-helper/reread-services hadoop