When I edited crontab on bash, everything is removed after reboot.
crond section<crond>
<custom_crontab>
<count>1</count>[......]# SPDX-License-Identifier: LGPL-2.1-or-later
#
# 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[......]yusian@Macbook ~ % sudo route change default 192.168.1.1
change net default: gateway 192.168.1.1
[……]
ubuntu@Server:~$ uname -a
Linux thinkpad 6.11.0-8-generic #8-Ubuntu SMP PREEMPT_DYNAMIC Mon Sep 16 13:41:20 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux
ubuntu@Server:~$ cat /proc/version
Linux version 6.11.0-8-generic (buildd@lcy02-amd64-042) (x86_64-linux-gnu-gcc-14 (U[......]library initialization failed - unable to allocate file descriptor table - out of memory
$ sudo vim /usr/lib/systemd/system/docker.service
>>>
#change this line
ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock
#to
ExecStart=/usr/bin/dockerd --de[......]