This is an original planning guide. It is not a vendor manual, an official standard, or legal advice. Example addresses use documentation ranges. Review every command before you paste it.
What this hour is for
df shows the filesystem. du shows directories. A filesystem can be out of inodes while bytes remain. The analyzer reads text you paste. The inode calculator uses numbers you type. Neither tool deletes a file or logs into a host.
Write the mount point and the largest directory you can name. Do not rm a path you do not recognize. Do not delete a database directory, a mail queue, or someone else's home because it was large.
The host is one you administer. If the paste contains secrets, redact them before they go in the ticket.
The change you can finish
Apply nothing while you are writing the note. When the lab window opens, it is one change on the host named in the ticket. Read the draft, then the host, then decide.
Rollback is the file, the package version, or the snapshot you saved first. You do not invent a rollback after the only copy is gone.
- Confirm the hostname and the mount.
- Paste df or du text you are allowed to hold, or type the numbers.
- Note bytes and inodes separately.
- Name the largest directory.
- Do not delete anything.
- Hand a deletion to its own ticket.
Mistakes that outlive the command
Disk Space Troubleshooting goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- A delete of an unknown directory.
- Inodes ignored.
- A database directory removed.
- The wrong host.
- Secrets left in the paste.
Decisions to write down
One decision for Disk Space Troubleshooting: Bytes and inodes are both written. The largest directory is named. Nothing was deleted. The host is yours. And secrets are redacted.
Checks before you call it done
Confirm this before you call the change done: The mount is written. Full means bytes or inodes, and the note says which. The large directory is named. No delete was done. And the next ticket is named or you stopped. If one of those fails, stop.
# Check inodes and bytes.
# Do not delete a directory you do not know.
# Redact secrets.Before you leave the host
Disk Space Troubleshooting ends when the hostname in the prompt matches the hostname in the ticket. If it does not, you are on the wrong host. Stop. A command that succeeded on the wrong host is not progress.
The draft stays a draft until a person has read the names in it. A generator does not log into the host and does not know which disk is empty. You delete a line that names a host, a path, or an account you did not write down.
192.0.2.10/24, gateway 192.0.2.1, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are documentation. example.com is a documentation name. They belong in the note. They are not values you leave on a host because a draft included them.
prompt-for-this is a reminder that a secret is missing. It is not a password, a key, or a token you save in the ticket or in git. The real secret stays in the password store.
One change is the window. If two things move and the result is wrong, you will not know which one did it. The next change waits for its own page.
If the same step fails twice, stop for the day. The failure is the result. Adding a forum command beside a half-applied change produces a host nobody can rebuild. Restore the copy you took first.
A second person reads the hostname and the change aloud. If they cannot find them in the ticket, the note is not done. Silence is not agreement. Then leave the host alone.
This page is a planning guide. It is not a vendor manual, not an official standard, and not permission to touch a host you do not administer. You do not disable a firewall, AppArmor, or SELinux to make a check pass.
Tools for this guide
These tools run in the browser on this site. They do not log into your machines.
Related pillar guides
More in this cluster
The pillar for this page, and the next published pages filed with it.