Exercise: Install, inspect and undo

Install, inspect and undo

• Search, inspect and install a package with dnf.
• Read the transaction summary and the dependencies.
• Review and undo a transaction.

Start the exercise

On workstation, start the exercise. It makes sure zip and unzip are not installed on servera.

[student@workstation ~]$ lab start sa-dnf

Later tasks assume that you are logged in to the server they name: ssh student@servera from workstation, then sudo -i for a root shell.

Find the package

On servera as root (sudo -i), confirm that zip is not installed. Search the repositories for it, and show its description.

[student@workstation ~]$ ssh student@servera
[student@servera ~]$ sudo -i
[root@servera ~]# zip
-bash: zip: command not found
[root@servera ~]# dnf search zip | head -6
...output omitted...
zip.x86_64 : A file compression and packaging utility compatible with PKZIP
[root@servera ~]# dnf info zip | head -8
Available Packages
Name         : zip
Version      : 3.0
Release      : 35.el9
Architecture : x86_64
Size         : 263 k
Source       : zip-3.0-35.el9.src.rpm
Repository   : baseos

Check the plan

Run dnf install zip, but answer no at the prompt. Which other package would be installed, and from which repository do both come?

[root@servera ~]# dnf install zip
Dependencies resolved.
================================================================================
 Package         Architecture      Version               Repository          Size
================================================================================
Installing:
 zip             x86_64            3.0-35.el9            baseos             263 k
Installing dependencies:
 unzip           x86_64            6.0-60.el9_8          baseos             180 k

Transaction Summary
================================================================================
Install  2 Packages

Total download size: 443 k
Installed size: 1.1 M
Is this ok [y/N]: n
Operation aborted.

Both packages come from baseos. Reading before agreeing is the habit to build.

Install it

Install the package for real, with -y, and use it.

[root@servera ~]# dnf install -y zip
...output omitted...
Installed:
  unzip-6.0-60.el9_8.x86_64                zip-3.0-35.el9.x86_64

Complete!
[root@servera ~]# cd /tmp && echo hello > a.txt && zip a.zip a.txt
  adding: a.txt (stored 0%)
[root@servera tmp]# unzip -l a.zip
Archive:  a.zip
  Length      Date    Time    Name
---------  ---------- -----   ----
        6  2026-10-03 17:27   a.txt
---------                     -------
        6                     1 file

Find where things came from

Which package provides /usr/bin/unzip? Use both rpm and dnf. Then list the files of zip that are documentation.

[root@servera tmp]# rpm -qf /usr/bin/unzip
unzip-6.0-60.el9_8.x86_64
[root@servera tmp]# dnf provides /usr/bin/unzip | head -3
unzip-6.0-60.el9_8.x86_64 : A utility for unpacking zip files
Repo        : @System
Matched from:
[root@servera tmp]# rpm -qd zip | head -3
/usr/share/doc/zip/CHANGES
...output omitted...

Read the history

Show the latest transactions, then the details of the install you made.

[root@servera tmp]# dnf history | head -4
ID     | Command line             | Date and time    | Action(s)      | Altered
-------------------------------------------------------------------------------
    11 | install -y zip           | 2026-10-03 17:27 | Install        |    2
[root@servera tmp]# dnf history info 11 | tail -6
Packages Altered:
    Install unzip-6.0-60.el9_8.x86_64 @baseos
    Install zip-3.0-35.el9.x86_64     @baseos

Undo it

Undo that transaction, and confirm that both packages are gone.

[root@servera tmp]# dnf history undo last -y
Removed:
  unzip-6.0-60.el9_8.x86_64                zip-3.0-35.el9.x86_64

Complete!
[root@servera tmp]# rpm -q zip unzip
package zip is not installed
package unzip is not installed
[root@servera tmp]# rm -f a.txt a.zip
[root@servera tmp]# exit
[student@servera ~]$ exit

Grade and finish

Check your work with lab grade sa-dnf, then put the exercise away with lab finish sa-dnf.