gentoo-overlay/net-firewall/ipset/files/ipset.systemd

[Unit]
Description=ipset service
Before=network-pre.target iptables.service ip6tables.service firewalld.service
Wants=network-pre.target
ConditionFileNotEmpty=/var/lib/ipset/rules-save

[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/usr/sbin/ipset -exist -file /var/lib/ipset/rules-save restore
ExecReload=/usr/sbin/ipset -exist -file /var/lib/ipset/rules-save restore
ExecStop=/usr/sbin/ipset -file /var/lib/ipset/rules-save save

[Install]
WantedBy=multi-user.target