Ubuntu系统init.d脚本启动依赖循环问题及预挂载配置咨询

阿华AIGC实验室

2026-5-15

解决init.d脚本依赖循环及磁盘挂载前执行的问题

我尝试将自定义脚本dudriver加入系统启动序列，该脚本需在挂载/etc/fstab中定义的磁盘前执行。/etc/init.d/dudriver脚本内容如下：

#!/bin/sh
# kFreeBSD do not accept scripts as interpreters, using #!/bin/sh and sourcing.
if [ true != "$INIT_D_SCRIPT_SOURCED" ] ; then
    set "$0" "$@"; INIT_D_SCRIPT_SOURCED=true . /lib/init/init-d-script
fi
### BEGIN INIT INFO
# Provides: dudriver
# Required-Start: $network $named
# Required-Stop: umountfs
# Should-Start: udev
# Should-Stop: udev
# X-Start-Before: mountall
# X-Stop-After: umountfs
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description:
# Description:
### END INIT INFO
if [ -x /opt/dudriver_startup.sh ]
then
    /opt/dudriver_startup.sh >>/var/log/dudriver_startup.log
fi
exit 0

多次编辑该脚本后执行命令出现如下错误：

root@sysman:/etc/init.d# update-rc.d dudriver remove
insserv: There is a loop between service umountfs and dudriver if stopped
insserv: loop involving service dudriver at depth 3
insserv: loop involving service umountfs at depth 2
insserv: loop involving service postgresql at depth 1
insserv: loop involving service cryptdisks at depth 4
insserv: loop involving service networking at depth 2
insserv: There is a loop between service umountfs and dudriver if stopped
insserv: loop involving service umountnfs at depth 3
insserv: exiting now without changing boot order!
update-rc.d: error: insserv rejected the script header

root@sysman:/etc/init.d# update-rc.d dudriver defaults
insserv: There is a loop between service umountfs and dudriver if stopped
insserv: loop involving service dudriver at depth 3
insserv: loop involving service umountfs at depth 2
insserv: loop involving service postgresql at depth 1
insserv: loop involving service cryptdisks at depth 4
insserv: loop involving service networking at depth 2
insserv: There is a loop between service umountfs and dudriver if stopped
insserv: loop involving service umountnfs at depth 3
insserv: exiting now without changing boot order!
update-rc.d: error: insserv rejected the script header

现存在两个问题：

如何解决服务间的依赖循环问题？
如何正确编写LSB头以实现dudriver脚本在磁盘挂载前执行？

系统信息：uname -a → Linux sysman 4.13.0-31-generic #34~16.04.1-Ubuntu SMP Fri Jan 19 17:11:01 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

1. 解决服务间的依赖循环问题

你遇到的循环错误根源在LSB头的停止依赖配置：你同时设置了Required-Stop: umountfs和X-Stop-After: umountfs，这会让insserv检测到停止序列的死锁——umountfs需要等dudriver停止，而dudriver又被要求在umountfs之后停止，形成了闭环。

修复步骤：

修改LSB头的停止依赖：删除冲突的停止配置项，因为你的脚本是启动时一次性执行，停止阶段不需要和umountfs绑定顺序。修改后相关配置如下：
```
# Required-Stop:
# Should-Stop:
# X-Stop-After:
```
强制移除旧的启动链接：因为当前依赖错误导致无法正常移除，用-f参数强制清理：
```
update-rc.d -f dudriver remove
```

2. 正确编写LSB头以实现磁盘挂载前执行

要让脚本在/etc/fstab定义的磁盘挂载前运行，核心是确保脚本在负责挂载处理的mountall服务之前启动，同时调整启动依赖避免冲突。

最终优化后的LSB头：

### BEGIN INIT INFO
# Provides: dudriver
# Required-Start: $syslog
# Required-Stop:
# Should-Start:
# Should-Stop:
# X-Start-Before: mountall
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: Load custom driver before disk mount
# Description: Executes /opt/dudriver_startup.sh to load custom drivers prior to mounting fstab-defined disks
### END INIT INFO

关键配置说明：

X-Start-Before: mountall：这是核心，明确告知insserv脚本要在mountall（处理fstab挂载的服务）之前启动
Required-Start: $syslog：只依赖基础的日志服务，因为你要写入日志到/var/log（根分区已提前挂载），避免依赖$network这类可能需要挂载后资源的服务
清空所有停止相关依赖：脚本仅在启动时执行，停止阶段无需特殊顺序