[Unit]
Description=DHCP interface %I
# We want to run after network.target so it doesn't try to bring
# up the interfaces a second time, but network-online should not
# be reached until after we've brought up the interfaces.
After=network.target
Before=network-online.target
Wants=network-online.target

ConditionPathExists=!/etc/sysconfig/network-scripts/ifcfg-%I

[Service]
Type=oneshot
User=root
ExecStartPre=/usr/local/sbin/dhcp-all-interfaces.sh %I
ExecStart=/sbin/ifup %I
RemainAfterExit=true
TimeoutStartSec=30s

[Install]
WantedBy=multi-user.target