Dangerous Commands

Read-only

Inspect Permissions Before Changing Them

A file or directory has a permission issue, but recursive fixes could break more than they repair.

Command

namei -l /var/www/example/index.html

Before you run this

System impact: Read-only. Low when scoped to the shown target.

When not to use it: Do not use inspection as the final fix; it only identifies where the permission problem is.

Expected output

A component-by-component permission and owner listing for the path.

System impact

Read-only. Nothing changes. The command shows permissions for each path component.

May require elevated permissions on protected paths or service-owned files.

Recovery / rollback: no state is changed.

When to use it

Use this before `chmod -R` or `chown -R` so you know which layer actually blocks access.

When not to use it

Do not use inspection as the final fix; it only identifies where the permission problem is.

Watch this command run

Command transcript

This sanitized transcript shows the commands and output shape without exposing host details.

demo@lab:~$

$ ls -l /var/www/example/index.html

-rw-r----- 1 root root 14 Jun 26 00:27 /var/www/example/index.html

$ namei -l /var/www/example/index.html

f: /var/www/example/index.html
drwxr-xr-x root root /
drwxr-xr-x root root var
drwxr-x--- root root www
drwxr-x--- root root example
-rw-r----- root root index.html

$ stat /var/www/example/index.html

  File: /var/www/example/index.html
  Size: 14        	Blocks: 8          IO Block: 4096   regular file
Device: 0,162	Inode: 4           Links: 1
Access: (0640/-rw-r-----)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2026-06-26 00:27:11.890296539 +0000
Modify: 2026-06-26 00:27:11.890296539 +0000
Change: 2026-06-26 00:27:11.892296562 +0000
 Birth: 2026-06-26 00:27:11.890296539 +0000

View commands shown

These are the commands shown in the sanitized transcript.

Commands shown

ls -l /var/www/example/index.html
namei -l /var/www/example/index.html
stat /var/www/example/index.html

next steps

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