systemd
Configuration
Slow boot, waiting for systemd-networkd-wait-online
By default, systemd-networkd-wait-online.service waits for all links it is
aware of and which are managed by systemd-networkd to be fully configured or
failed, and for at least one link to be online.
If your system has multiple network interfaces, but some are not expected to be
connected all the time (e.g. if you have a dual-port Ethernet card, but only one
cable plugged in), starting systemd-networkd-wait-online.service will fail
after the default timeout of 2 minutes. This may cause an unwanted delay in the
startup process.
To change the behaviour to wait for any interface rather than all interfaces to
become online, edit the service and add the --any parameter to the ExecStart
line:
$ cat /etc/systemd/system/network-online.target.wants/systemd-networkd-wait-online.service
# SPDX-License-Identifier: LGPL-2.1+
#
# This file is part of systemd.
#
# systemd is free software; you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
[Unit]
Description=Wait for Network to be Configured
Documentation=man:systemd-networkd-wait-online.service(8)
DefaultDependencies=no
Conflicts=shutdown.target
Requires=systemd-networkd.service
After=systemd-networkd.service
Before=network-online.target shutdown.target
[Service]
Type=oneshot
ExecStart=/lib/systemd/systemd-networkd-wait-online --any
RemainAfterExit=yes
[Install]
WantedBy=network-online.target
Note
This issue occurs on the Helios64.
Source: wiki.archlinux.org
Restart service after X amount of time
Let's assume one needs to restart service X every hour. Instead of using a
CRON job, the following lines could simply be added to the systemd service
unit file:
[Service]
RuntimeMaxSec=<seconds after which to restart>
Restart=always