System Setting Other Debugs (系统设置其它排错)

February 6, 2026February 6, 2026

[排错] 解决 Linux 启动时某些服务没有开机自启（日志里报错： “deleted to break ordering cycle starting”）

报错代码

某些服务没有开机自启例如 NetworkManager.service

原因分析

在系统日志里可以类似 …… Job network.target/start deleted to break ordering cycle starting with …… 报错例如：

# cat /var/log/messages
Jan 1 10:09:24 server systemd[1]: network-online.target: Found ordering cycle on network.target/start
Jan 1 10:09:24 server systemd[1]: network-online.target: Found dependency on NetworkManager.service/start
Jan 1 10:09:24 server systemd[1]: network-online.target: Found dependency on basic.target/start
Jan 1 10:09:24 server systemd[1]: network-online.target: Found dependency on slices.target/start
Jan 1 10:09:24 server systemd[1]: network-online.target: Found dependency on mysql.slice/start
Jan 1 10:09:24 server systemd[1]: network-online.target: Found dependency on remote-fs.target/start
Jan 1 10:09:24 server systemd[1]: network-online.target: Found dependency on remote-fs-pre.target/start
Jan 1 10:09:24 server systemd[1]: network-online.target: Found dependency on iscsi.service/start
Jan 1 10:09:24 server systemd[1]: network-online.target: Found dependency on network-online.target/start
Jan 1 10:09:24 server systemd[1]: network-online.target: Job network.target/start deleted to break ordering cycle starting with network-online.target/start
Jan 1 10:09:24 server systemd[1]: NetworkManager-wait-online.service: Found ordering cycle on NetworkManager.service/start
Jan 1 10:09:24 server systemd[1]: NetworkManager-wait-online.service: Found dependency on basic.target/start
Jan 1 10:09:24 server systemd[1]: NetworkManager-wait-online.service: Found dependency on slices.target/start
Jan 1 10:09:24 server systemd[1]: NetworkManager-wait-online.service: Found dependency on mysql.slice/start
Jan 1 10:09:24 server systemd[1]: NetworkManager-wait-online.service: Found dependency on remote-fs.target/start
Jan 1 10:09:24 server systemd[1]: NetworkManager-wait-online.service: Found dependency on remote-fs-pre.target/start
Jan 1 10:09:24 server systemd[1]: NetworkManager-wait-online.service: Found dependency on iscsi.service/start
Jan 1 10:09:24 server systemd[1]: NetworkManager-wait-online.service: Found dependency on network-online.target/start
Jan 1 10:09:24 server systemd[1]: NetworkManager-wait-online.service: Found dependency on NetworkManager-wait-online.service/start
Jan 1 10:09:24 server systemd[1]: NetworkManager-wait-online.service: Job NetworkManager.service/start deleted to break ordering cycle starting with NetworkManager-wait-online.service/start

从案例中日志里的内容可以判断：
1) network.target/NetworkManager.service 启动
2) NetworkManager.service 作为基础服务依赖 basic.target
3) basic.target 依赖所有 slice 包括 mysql.slice
4) mysql.slice 依赖 iscsi.service/remote-fs.target/remote-fs-pre.target
5) iscsi.service/remote-fs.target/remote-fs-pre.target 依赖 network.target/NetworkManager.service
6) 系统为了防止启动时陷入死循环，systemd 报错 Job NetworkManager.service/start deleted to break ordering cycle 并放弃启动 NetworkManager.service

解决方法

取消不太重要的服务的依赖要求

# vi /etc/systemd/system/mysql.slice

将以下内容：

......
Before=slices.target
Wants=-.slice
After=-.slice remote-fs.target
......

修改为：

......
Before=slices.target
Wants=-.slice
After=-.slice remote-fs.target
......

（补充：这里以取消使用 /etc/systemd/system/mysql.slice 文件的服务的依赖要求为例）

January 13, 2026January 25, 2026

[排错] 解决 Linux 开机时报错 “kernel panic – no syncing: Attempted to kill init ……”

报错代码

/init: error while loading shared libraries: libsystemd-shared-239.so: cannot open shared object file: No such file or directory
kernel panic - no syncing: Attempted to kill init! exitcode=0x00007f00

解决方法

步骤一：进入拯救模式

Linux 救援模式的进入

步骤二：确认第三方软件库

2.1 搜集第三方软件库信息

# ldconfig -p > /tmp/ldconfig.out

2.2 确认有没有第三方软件库

# for l in $(awk '{ print $1 }' /tmp/ldconfig.out); do matches=$(awk "\$1 == \"$l\" { print }" /tmp/ldconfig.out); if [ $(echo "$matches" | wc -l) -ge 2 ]; then echo "$matches"; echo; fi; done

（补充：如果没有第三方软件库的话这里不会有任何输出）

步骤三：检查 /etc/ld.so.conf 文件或者 /etc/ld.so.conf.d/ 目录里的文件去除第三方库

（步骤略）

步骤四：刷新库缓存

# ldconfig

步骤五：为启动失败的系统创建创建 initramfs 文件

# dracut -f /boot/initramfs-(uname -r).img $(uname -r)

（补充：这里以将正在运行的内核版本生成一个新的 initramfs 为例）

（注意：此时原来启动系统时使用的那个 initramfs 文件会被覆盖）

步骤六：重启系统

# reboot

参考文献

https://access.redhat.com/solutions/7096246

March 31, 2025January 25, 2026

[排错] Linux 解决启动网络服务时，报错 “SIOCADDRT: File Exists”

报错代码

SIOCADDRT: File Exists

解决方法

确保以下目录中，网卡配置文件的 IP 地址只出现过了 1 次

/etc/sysconfig/network-scripts

March 26, 2025December 31, 2025

[排错] Linux 解决使用 authselect apply-changes 命令时报错 “[error] [……] has unexpected content!”

报错命令

# authselect apply-changes

报错代码

[error] [/....../system-auth] has unexpected content!
[error] [/....../password-auth] has unexpected content!
[error] [/....../nsswitch.conf] has unexpected content!
[error] Unexpected changes to the configuration were detected.
[error] Refusing to activate profile unless those changes are removed or overwrite is requested.
Some unexpected changes to the configuration were detected. Use 'select' command instead.

解决方法

创建新的 authselect 文件

步骤一：移走原来的 authselect 文件

# mv /etc/authselect/custom/password-policy /etc/authselect/custom/password-policy-backup

步骤二：创建新的 authselect 的文件

# authselect create-profile password-policy -b sssd --symlink-meta --symlink-pam

步骤三：使用新创建的 authselect 文件

# authselect select custom/password-policy with-sudo with-faillock without-nullok with-mkhomedir --force

步骤四：启用 oddjob 服务

# dnf install oddjob ; systemctl enable --now oddjobd.service

步骤五：启用新的 authselect 文件

# authselect apply-changes

March 14, 2025December 31, 2025

[排错] Linux 解决使用 setfacl 命令时报错 “setfacl: …… : Operation not supported”

报错命令

# setfacl ......

报错代码

setfacl: ......: Operation not supported

解决方法

添加 acl 参数

临时解决方法（临时在挂载时添加 acl 参数）：

# mount -o remount,acl /mnt

（补充：这里以给挂载的 /mnt 目录添加 acl 参数为例）

永久解决方法（永久在挂载时添加 acl 参数）：

# vi /etc/fstab

将部分内容修改如下：

......
/dev/sda5 /mnt xfs defaults,acl 0 0
......

（补充：这里以给从硬盘 /dev/sda5 挂载到 /mnt 目录的目录添加 acl 参数为例）