[Unit]
Description=Create Persistent Log Directory on /storage and rotate large logs
DefaultDependencies=no
RequiresMountsFor=/storage

[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/bin/mkdir -p /storage/.cache/log/journal /storage/.cache/journald.conf.d ; \
/usr/bin/find /storage/.cache/log/ -maxdepth 1 -type f -size +512k ! -name '*.old' -exec mv {} {}.old \;
