Apt sources, updates and extra tools

Proxmox VE 9.0 runs on Debian 13 “trixie”

Remember that your Proxmox VE 9.0 runs on a Debian GNU Linux version 13 (trixie). You can check the Debian version in the /etc/os-release file found in the system.

Editing the apt repository sources

Proxmox VE comes with its apt system configured to point at two repositories for enterprise subscriptions, one for Proxmox VE itself while the other is for the Proxmox version of the Ceph distributed storage system. This is a problem because, unless you already have such subscription, you will not be able to perform system updates at all. Look what happens if, in a root shell, you try to execute apt update with the default setup:

$ apt update
Get:1 http://security.debian.org/debian-security trixie-security InRelease [43.4 kB]
Hit:2 http://deb.debian.org/debian trixie InRelease       
Get:3 http://deb.debian.org/debian trixie-updates InRelease [47.1 kB]
Get:4 http://security.debian.org/debian-security trixie-security/main amd64 Packages [11.6 kB]
Get:5 http://security.debian.org/debian-security trixie-security/main Translation-en [10.6 kB]
Err:6 https://enterprise.proxmox.com/debian/ceph-squid trixie InRelease          
  401  Unauthorized [IP: 51.91.38.34 443]
Err:7 https://enterprise.proxmox.com/debian/pve trixie InRelease
  401  Unauthorized [IP: 51.91.38.34 443]
Error: Failed to fetch https://enterprise.proxmox.com/debian/ceph-squid/dists/trixie/InRelease  401  Unauthorized [IP: 51.91.38.34 443]
Error: The repository 'https://enterprise.proxmox.com/debian/ceph-squid trixie InRelease' is not signed.
Notice: Updating from such a repository can't be done securely, and is therefore disabled by default.
Notice: See apt-secure(8) manpage for repository creation and user configuration details.
Error: Failed to fetch https://enterprise.proxmox.com/debian/pve/dists/trixie/InRelease  401  Unauthorized [IP: 51.91.38.34 443]
Error: The repository 'https://enterprise.proxmox.com/debian/pve trixie InRelease' is not signed.
Notice: Updating from such a repository can't be done securely, and is therefore disabled by default.
Notice: See apt-secure(8) manpage for repository creation and user configuration details.

See the lines like the Err:6 one indicating an error in the process. Without a valid enterprise subscription, your system is Unauthorized to get updates from Proxmox’s enterprise repository.

Changing the apt repositories

You need to disable the enterprise repositories and enable the repository for non-subscribers:

1. Access your Proxmox VE web console as root, and browse to your pve node’s Updates > Repositories section:

   

   Notice the yellow warnings about having the enterprise repositories enabled with no active subscription. This is related to the warning you saw when you logged in the web console.

2. Notice that there are two enterprise repositories, one for the Ceph distributed storage technology embedded in Proxmox while the other is for Proxmox VE itself. You have to disable both:

   Begin with the Ceph enterprise repository, the one with the URI https://enterprise.proxmox.com/debian/ceph-squid:

   

   See that the Disable button is now active, so press it to disable the enterprise repository. Then, do the same with the other enterprise repository, the one for Proxmox VE with the URI https://enterprise.proxmox.com/debian/pve:

   

3. With both Proxmox enterprise repositories disabled, the web console warns you that you will not get any updates for your Proxmox VE platform:

   

4. Click on the Add button now. The web console prompts the same warning you saw when you logged in:

   

   Click on OK to open the window where you can add apt repositories:

   

5. On that window, choose the No-Subscription option from the Repository list and then press on Add:

   

6. With the No-Subscription repository added, you see a different status in the Repositories screen:

   

   What the new warning means is that the no-subscription repository is not the safest one to use for real production use. Regardless, it should be good enough for your personal homelab needs.

Update your system

Now you can browse to the Updates screen and see what is pending:

1. Browse to the Updates tab, and click on the Refresh button to be sure that you are getting the most recent list of updates:

   

   Pressing the refresh button will launch again the warning window about not having a valid subscription:

   

   Close that window and meet a new one in which you can see the apt update task’s progress:

   

   When you see the line TASK OK, close the window to go back to the updates list:

   

   See above that there are a number of updates, from different origins, to be applied. In future attempts, this page will show a different selection of pending packages or none at all.

2. To apply all the updates, click on the Upgrade button:

   

3. By default, the web console opens a noVNC shell console, using your root user, in which it launches the apt dist-upgrade command:

   

   Important

   Pay attention to when the apt command requests your confirmation to proceed!
   Also, be aware that some packages may require your input for some reason or other.

4. When the apt command finishes, it returns the control to the prompt within the shell console:

   

   Type exit to logout from the shell console and close its window, or just close the window directly:

   

5. Back in the Updates view of your pve node, see that the updates list has not been refreshed. Press again on the Refresh button to update the list:

   

6. The Updates view may or may not show more updates to apply after refreshing. Keep on applying the upgrades until none appears listed in this page:

   

7. If you have applied many updates, or if some of them were kernel-related, it is better if you reboot the system. Just press on the Reboot button while having your pve node selected:

   

   The Proxmox VE web console asks your confirmation. Click on Yes to proceed:

   

8. After the reboot, just log back in the web console as root and check that Proxmox VE still runs fine.

Consideration about upgrades

As you have seen before, you can end having to apply several updates at once in your system. In theory, a good administrator has to be diligent and verify that each update is safe to apply. In reality, trying to do that is not possible. Still, you should at least be aware of the updates that directly affect the Proxmox VE platform, the ones that can update to a more recent minor or major version. Those are the ones that could break things in your setup, specially the major ones (for instance, when going from a version 8.y.z to a 9.y.z one).

Since you only have one standalone node, before you apply such updates, you should make a clone of your only node’s Proxmox VE root filesystem (or the entire drive) with a tool like Clonezilla. This way, if something goes south in the upgrade, you can always go back to the previous stable state.

You can use apt directly

Instead of using the Updates screen in the web console, you can use the apt command directly through an SSH shell or by opening a shell directly from the web console.

If you prefer to open the shell from the Proxmox VE web console, know that it offers three different options:

The best option is the xterm.js shell, since it allows you to copy and paste, unlike the noVCN one. SPICE does not open you a shell, it gives you a file that you have to use in a special client prepared to use the SPICE protocol.

Installing useful extra tools

Now that you can use the apt command properly, it is time to install some useful tools for different purposes:

• htop
  Interactive text-based process viewer, similar to top but much more user friendly and colorful (on terminals that support color).

• net-tools
  Package that includes several useful commands for network management.

• sudo
  A command that allows a system administrator to give limited root privileges to users and log root activity.

• tree
  Is a recursive directory listing command that produces a depth indented listing of files.

• vim
  A more complete version of the vi editor, which includes fancy features like syntax coloring.

To install all of the above at once, open a shell terminal as root and use the following command:

$ apt install -y htop net-tools sudo tree vim

Utilities for visualizing sensor information

Any modern computer comes with a bunch of integrated sensors, usually ones that return CPU’s cores temperatures, fan speeds and voltages. Sure you would like to see those values through the shell easily, right? There is a bunch of tools that give such information, but this guide proposes you two quite interesting ones.

The lm_sensors package

The lm_sensors package provides a sensors command that allows you to see the values returned by the sensors integrated in a Linux host like your PVE server.

To be able to use the sensors command, you need to install and configure the lm_sensors package as follows:

1. Open a shell in your main pve node as root (or as a sudo-able user if you already got one), then execute the next apt command:

   $ apt install -y lm-sensors

2. Execute sensors-detect. This launches a scan on your system looking for all the sensors available in it, so it can determine which kernel modules lm_sensors has to use. This scan is automatic, but the command asks you on every step of the procedure:

   Warning

   Some steps might give trouble if executed in your system!
   Read the question asked on each step and, in case of doubt, answer no to the step you feel unsure of.

   # sensors-detect version 3.6.2
   # System: Packard Bell iMedia S2883
   # Kernel: 6.14.8-2-pve x86_64
   # Processor: Intel(R) Celeron(R) CPU J1900 @ 1.99GHz (6/55/8)
   
   This program will help you determine which kernel modules you need
   to load to use lm_sensors most effectively. It is generally safe
   and recommended to accept the default answers to all questions,
   unless you know what you're doing.
   
   Some south bridges, CPUs or memory controllers contain embedded sensors.
   Do you want to scan for them? This is totally safe. (YES/no): 
   Module cpuid loaded successfully.
   Silicon Integrated Systems SIS5595...                       No
   VIA VT82C686 Integrated Sensors...                          No
   VIA VT8231 Integrated Sensors...                            No
   AMD K8 thermal sensors...                                   No
   AMD Family 10h thermal sensors...                           No
   AMD Family 11h thermal sensors...                           No
   AMD Family 12h and 14h thermal sensors...                   No
   AMD Family 15h thermal sensors...                           No
   AMD Family 16h thermal sensors...                           No
   AMD Family 17h thermal sensors...                           No
   AMD Family 15h power sensors...                             No
   AMD Family 16h power sensors...                             No
   Hygon Family 18h thermal sensors...                         No
   AMD Family 19h thermal sensors...                           No
   Intel digital thermal sensor...                             Success!
       (driver `coretemp')
   Intel AMB FB-DIMM thermal sensor...                         No
   Intel 5500/5520/X58 thermal sensor...                       No
   VIA C7 thermal sensor...                                    No
   VIA Nano thermal sensor...                                  No
   
   Some Super I/O chips contain embedded sensors. We have to write to
   standard I/O ports to probe them. This is usually safe.
   Do you want to scan for Super I/O sensors? (YES/no): 
   Probing for Super-I/O at 0x2e/0x2f
   Trying family `National Semiconductor/ITE'...               No
   Trying family `SMSC'...                                     No
   Trying family `VIA/Winbond/Nuvoton/Fintek'...               No
   Trying family `ITE'...                                      Yes
   Found `ITE IT8772E Super IO Sensors'                        Success!
       (address 0xa30, driver `it87')
   Probing for Super-I/O at 0x4e/0x4f
   Trying family `National Semiconductor/ITE'...               No
   Trying family `SMSC'...                                     No
   Trying family `VIA/Winbond/Nuvoton/Fintek'...               No
   Trying family `ITE'...                                      No
   
   [...]
   
   Next adapter: i915 gmbus dpb (i2c-5)
   Do you want to scan it? (yes/NO/selectively): yes
   
   Next adapter: i915 gmbus dpd (i2c-6)
   Do you want to scan it? (yes/NO/selectively): yes
   
   Next adapter: AUX B/DP B (i2c-7)
   Do you want to scan it? (yes/NO/selectively): yes
   
   
   Now follows a summary of the probes I have just done.
   Just press ENTER to continue: 
   
   Driver `it87':
   * ISA bus, address 0xa30
       Chip `ITE IT8772E Super IO Sensors' (confidence: 9)
   
   Driver `coretemp':
   * Chip `Intel digital thermal sensor' (confidence: 9)
   
   To load everything that is needed, add this to /etc/modules:
   #----cut here----
   # Chip drivers
   coretemp
   it87
   #----cut here----
   If you have some drivers built into your kernel, the list above will
   contain too many modules. Skip the appropriate ones!
   
   Do you want to add these lines automatically to /etc/modules? (yes/NO)yes
   Successful!
   
   Monitoring programs won't work until the needed modules are
   loaded. You may want to run '/etc/init.d/kmod start'
   to load them.
   
   Unloading cpuid... OK

   A big chunk of the sensors-detect command’s output has been omitted since it resulted to be very long in this guide’s reference hardware. Still, know that all but one of the steps were executed without issues. See how the final question asks for your permission to write some lines in the /etc/modules file. Say yes to it, but bear in mind that, if you uninstall the lm_sensors package later, those lines will remain written in /etc/modules.

   Below you can see the lines sensors-detect wrote in the /etc/modules file of this guide’s PVE host. Bear in mind that these lines may be different in your system:

   # /etc/modules is obsolete and has been replaced by /etc/modules-load.d/.
   # Please see modules-load.d(5) and modprobe.d(5) for details.
   #
   # Updating this file still works, but it is undocumented and unsupported.
   
   # Generated by sensors-detect on Wed Aug 20 10:57:42 2025
   # Chip drivers
   coretemp
   it87

   Note

   The /etc/modules file has been replaced by the /etc/modules-load.d/ directory
   Notice the related warning about this change at the beginning of the /etc/modules file. If you check inside the /etc/modules-load.d/ directory, you will find a modules.conf symlink file pointing to the /etc/modules file ensuring backwards compatibility with packages that still have not adapted to this change like lm_sensors.

3. To ensure that all the modules configured by sensors-detect are loaded, reboot your system:

   $ reboot

4. After the reboot, open a new shell and try the sensors command:

   $ sensors
   soc_dts1-virtual-0
   Adapter: Virtual device
   temp1:        +36.0°C  
   
   it8772-isa-0a30
   Adapter: ISA adapter
   in0:         708.00 mV (min =  +2.56 V, max =  +1.22 V)  ALARM
   in1:           1.37 V  (min =  +1.50 V, max =  +0.84 V)  ALARM
   in2:           2.06 V  (min =  +1.69 V, max =  +2.46 V)
   in3:           2.00 V  (min =  +2.05 V, max =  +2.63 V)  ALARM
   in4:           2.03 V  (min =  +2.27 V, max =  +2.18 V)  ALARM
   in5:           2.03 V  (min =  +1.24 V, max =  +0.76 V)  ALARM
   in6:           2.98 V  (min =  +1.78 V, max =  +1.32 V)  ALARM
   3VSB:          3.36 V  (min =  +4.66 V, max =  +2.90 V)  ALARM
   Vbat:          3.26 V  
   fan2:           0 RPM  (min =   32 RPM)  ALARM
   fan3:        1555 RPM  (min =   14 RPM)
   temp1:        +31.0°C  (low  = +61.0°C, high = -11.0°C)  ALARM  sensor = thermistor
   temp2:        +34.0°C  (low  = -17.0°C, high = -93.0°C)  sensor = thermistor
   temp3:        -70.0°C  (low  = +127.0°C, high =  -2.0°C)  sensor = Intel PECI
   pwm1:             64%  (freq = 23437 Hz)  MANUAL CONTROL
   pwm2:             64%  (freq = 23437 Hz)
   pwm3:             58%  (freq = 23437 Hz)
   intrusion0:  ALARM
   
   acpitz-acpi-0
   Adapter: ACPI interface
   temp1:        +37.0°C  
   
   soc_dts0-virtual-0
   Adapter: Virtual device
   temp1:        +35.0°C  
   
   coretemp-isa-0000
   Adapter: ISA adapter
   Core 0:       +34.0°C  (high = +105.0°C, crit = +105.0°C)
   Core 1:       +34.0°C  (high = +105.0°C, crit = +105.0°C)
   Core 2:       +35.0°C  (high = +105.0°C, crit = +105.0°C)
   Core 3:       +35.0°C  (high = +105.0°C, crit = +105.0°C)

   Notice how the command outputs all sorts of information from the system: different temperature measurements from different adapters and interfaces, the speed of the fans present in the host and also some voltage information. Also see how the command has printed ALARM on several lines, which are warnings of things the command is finding odd. Since this guide’s host is working fine, this is more probably a question of configuring the command so it evaluates the values properly. As you may imagine, the output of this command will be quite different in your machine.

The Stress Terminal UI: s-tui

The Stress Terminal UI, or just s-tui, is a command that gives you a much more graphical vision of the current performance of your hardware. To get it, just install its package with apt:

$ apt install -y s-tui

With the package installed, just execute the s-tui command:

$ s-tui

You should see the main screen of s-tui immediately:

You can use the arrows or the Page Up/Down keys to browse in the left-side menu and even change some options. Going down in the menu, you can see all the sensors this command is able to read. The settings of s-tui are kept in the user’s .config/s-tui folder.

Relevant system paths

Directories

• $HOME/.config/s-tui
• /etc/
• /etc/modules-load.d/

Files

• /etc/modules
• /etc/modules-load.d/modules.conf

References

Proxmox

• Proxmox VE Wiki
  • Proxmox Package Repositories
  • Proxmox VE No-Subscription Repository
  • Roadmap

Proxmox VE related contents

• Blog-D without Nonsense. How to: Fix Proxmox/PVE update failed(Failed to fetch 401 Unauthorized) (TASK ERROR: command ‘apt-get update’ failed: exit code 100)

System tools

• Ceph
• Clonezilla
• Find fan speed and cpu temp in Linux
• Lm-sensors: Monitoring CPU And System Hardware Temperature
• Lm_sensors - Linux hardware monitoring
• The lm-sensors package on GitHub
• The Stress Terminal UI: s-tui on GitHub