nmcli device status UNMANAGED on Ubuntu 20.04 Jammy

Changing NIC from Unmanaged to Managed State in Ubuntu

Before creating a teaming NIC on Ubuntu, ensure that the ethernet interfaces are in a managed state. This guide walks you through how to change the state from unmanaged to managed.

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Step 1 — Check Netplan Configuration

ls /etc/netplan/
# if config file is 00-network-manager-all.yaml
cat /etc/netplan/00-network-manager-all.yaml

Step 2 — Display Network Device Status

nmcli device

Note: Identify devices that show STATE = unmanaged and note their DEVICE and TYPE.

Step 3 — Check for Unmanaged Devices

sudo grep -ri unmanaged-devices /etc/NetworkManager/conf.d/
sudo grep -ri unmanaged-devices /etc/NetworkManager/

Make sure your device is not listed under unmanaged-devices.

Step 4 — Edit Global NetworkManager Configuration

sudo vim /usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf

Add ethernet to the managed list by modifying the file like this:

[keyfile]
unmanaged-devices=*,except:type:ethernet

Then reload the NetworkManager service:

sudo systemctl reload NetworkManager.service

Step 5 — Verify the Device State

nmcli device
nmcli connection show

Step 6 — Restart Networking

nmcli networking off
nmcli networking on

Step 7 — Test Connectivity

nmcli connection up eno1

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✅ Tip: Once your NIC shows as managed, you can proceed to configure NIC teaming using netplan or nmcli.

Source: nixcraft.com

H3C Hardware Device Management (HDM)

H3C HDM — Hardware Device Management

Built‑in system for H3C servers enabling remote monitoring, control, and maintenance of server hardware.

🔧 Functions — What it does

Remote hardware management: diagnostics, sensor monitoring, power control, and web interface.

• Server diagnostics & alerts
• Sensor data: temperature, fan, voltage
• Power on/off, reboot, schedule
• Web UI for component management

💡 Capabilities — Key features

Remote KVM, virtual media, and support for IPMI and Redfish standards.

• Remote KVM (keyboard, video, mouse)
• Virtual media for ISO mounting
• IPMI & Redfish API support
• SNMP/Trap monitoring integration

🎯 Purpose — Why it matters

Provides intelligent, efficient, and reliable management from single servers to data centers.

• Simplify O&M workflows
• Enable automation & orchestration
• Reduce downtime & improve performance

Serial Number Commands

Get Serial Number — Commands for Desktops, Servers & Network Devices

Copy the commands from the boxes and run them on the target machine. This HTML uses no JavaScript (improves Blogger Compose compatibility). Expand each section for commands and notes.

Windows (Desktop & Server)PowerShell & WMIC

Works on Windows 7 / 8 / 10 / 11 and Windows Server (2008+). Run as Administrator when required.

Commands

Tip: Click inside a box, Ctrl+A then Ctrl+C to copy

PowerShell (Get-CimInstance)

Get-CimInstance -ClassName Win32_BIOS | Select-Object SerialNumber

PowerShell (alternate)

Get-WmiObject -Class Win32_BIOS | Select-Object SerialNumber

Legacy WMIC (works in many environments)

wmic bios get serialnumber

From registry (example)

reg query HKEY_LOCAL_MACHINE\\HARDWARE\\DESCRIPTION\\System\\BIOS /v SystemSerialNumber

If commands return blank on virtual machines the host/BIOS might not expose serial number (VMs often show 'None' or empty).

Linux (Desktop & Server)dmidecode / sysfs

Commands below require root privileges for dmidecode and reading /sys files on many systems.

Commands

Run as root or prepend sudo where shown

dmidecode

sudo dmidecode -s system-serial-number

Alternative via sysfs (Linux kernel)

cat /sys/class/dmi/id/product_serial\n# or\ncat /sys/class/dmi/id/board_serial

Using lshw (if installed)

sudo lshw -class system | grep -i serial

Red Hat / CentOS note

sudo dmidecode -t system

On cloud instances or some small form-factor devices the DMI table may be absent or have vendor-specific fields.

macOS (Apple desktop & server)system_profiler / ioreg

Run on the Mac where the hardware is physically present.

Commands

system_profiler

system_profiler SPHardwareDataType | awk '/Serial/ {print $4}'\n# Or fuller info\nsystem_profiler SPHardwareDataType

ioreg method

ioreg -l | grep IOPlatformSerialNumber\n# or\n/usr/sbin/ioreg -c IOPlatformExpertDevice | awk -F'\"' '/IOPlatformSerialNumber/ {print $4}'

Cisco IOS (routers & switches)show commands

Run from privileged EXEC mode (enable).

Commands

Basic (shows Processor board ID / serial)

show version

Inventory (detailed, modular devices)

show inventory\n# On some platforms\nshow platform chassis serial\nshow platform hardware qfp active infrastructure sysid

Look for lines like Processor board ID XXXXXXXXX or serial entries in the inventory output.

Juniper Junosshow chassis

Run from CLI in operational mode.

Commands

show chassis hardware | match Serial\n# or\nshow system information | match serial

Other Unix variantsAIX / Solaris / FreeBSD / HP-UX

Commands below vary by vendor. Run as root when required.

Commands

OS	Command (examples)
AIX	lsattr -El sys0 | grep -i systemid\n# or\nlscfg -vp | grep -i serial
Solaris (SPARC/x86)	prtdiag -v | grep -i serial\n# or\n/usr/sbin/smbios -s system-summary
FreeBSD	dmidecode -s system-serial-number\n# or\nkenv -q smbios.system.serial
HP-UX	# On many HP systems\n/opt/hp/hpuxinfo/bin/serialnumber (vendor tool)\n# Or check SAM or iLO for servers; vendor utilities vary

If OS-level commands do not show serial, check vendor management interfaces (ILO, DRAC, IMM) or hardware labels.

Quick troubleshooting & best practice

• Run commands as an administrator/root where noted (use sudo for Linux).
• Virtual machines often do not expose a hardware serial number; check hypervisor or cloud metadata service instead.
• For servers, management controllers (iLO, DRAC, IMM) reliably show chassis serial numbers from the vendor.
• If a command returns nothing, try alternate commands in the same section — vendors differ.

Linux : Showing Processor Type, Memory Size, Total Disk Space

Anyway, to cut a long story short, I got documentation that needs to be submitted which is to get the info of the processor type, memory info and storage size for Linux machines. 

A bunch of information will be displayed if we only used lscpu, meminfo and df command. To make life easier, below are the straightforward command to get that information.

Checking for processor type.

(1) lscpu | grep "Model name"

Checking memory info using grep command.
(Global Regular Expression Print)

(2) grep MemTotal /proc/meminfo | numfmt --field 2 --from-unit=Ki --to-unit=Mi | sed 's/ kB/M/g'

(3) grep MemTotal /proc/meminfo | numfmt --field 2 --from-unit=Ki --to=iec | sed 's/ kB//g'

(4) grep MemTotal /proc/meminfo | numfmt --field 2 --from-unit=Ki --to-unit=Gi | sed 's/ kB/G/g'

Checking memory info using awk command.
(Aho, Weinberger, Kernighan (authors))

(5) awk '$3=="kB"{$2=$2/1024;$3="MB"} 1' /proc/meminfo | column -t | grep MemTotal

(6) awk '$3=="kB"{$2=$2/1024^2;$3="GB";} 1' /proc/meminfo | column -t | grep MemTotal

Checking Store Size

(7) df --total -h

If there is any detailed explanation, just let me know in the comment below. Thanks.

MikroTik Variable for sharing.

I'm trying to find the documentation for extracting data from the database from Mikrotik. Unfortunately, this is what I get on the date 12 April 2022.

Thanks to sergejs from MikroTik Support posting way back in the year 2005. Most of the variables are still usable. Hopefully, this will help you do your customization.

 _username - Username

u_password - Password
u_firstName - First name
u_lastName - Last name
u_phone - Phone
u_location - Location
u_comment - Comment
u_email - Email
u_ipAddr - IP address
u_callerId - Caller ID
u_shared_users - Shared users
u_usedUpload - Upload Used
u_usedDownload - Download Used
u_usedUptime - Uptime Used
u_lastIpAddr - Last used IP
u_lastMAC - Last used MAC
u_tillTime - Till time
u_timeLeft - Total time left
u_actualProfileName - Actual profile
u_actualProfileStart - Start time
u_actualProfileEnd - End time
u_actualProfileLeft - Time left
u_limitDownload - Download limit
u_limitUpload - Upload limit
u_limitDownload - Transfer limit
u_limitUptime - Uptime Limit
u_actualRateLim - Rate limit
u_moneyPaid - Money paid
u_moneyUsed - Money used
u_moneyLeft - Money left
u_wirelessPsk - Preshared key
u_wirelessEncKey - Encryption key
u_wirelessEncAlgo - Encryption algorithm

If there are any updates from the list above, let me know ok.

How to Fix Write-Protected Read-Only Drives

There are lots of guide for unlock drive that is WRITE PROTECTED, but most of the guide are for drives that have Write Protect Switch. What if the drives does not have any kind of switch?

1. Open Command Prompt, right-click - Run as administrator
2. When the command console opens, type DISKPART
3. List the drives by typing LIST DISK  
4. Select the USB drive by typing  SELECT DISK 1 (if disk 1 is your USB drive)
5. Inspect the details for that disk by typing  DETAIL DISK
   Check if the disk is marked as Read-only - e.g.

DISKPART > DETAIL DISK
TOSHIBA MK2559GSXP USB Device
Disk ID: EF78DCD3
Type   : USB
Status : Online
Path   : 0
Target : 0
LUN ID : 0
Location Path : UNAVAILABLE
Current Read-only State : Yes
Read-only  : Yes
Boot Disk  : No
Pagefile Disk  : No
Hibernation File Disk  : No
Crashdump Disk  : No
Clustered Disk  : No

  Volume ###  Ltr  Label        Fs     Type        Size     Status     Info
  ----------  ---  -----------  -----  ----------  -------  ---------  --------
  Volume 5     H   RMPARTUSB    NTFS   Partition    232 GB  Healthy

Note: It is also possible to mark a volume as read-only, so try  LIST VOLUME and SELECT VOLUME F: (where F: is your USB drive letter) and then DETAIL VOLUME to list the attributes.

**If it says 'Read-only: NO' in Diskpart but shows as 'Read-Only' in Disk Manager, then the disk is probably physically write-protected (or perhaps write-protected by the firmware in the device's internal controller). In this case the following procedure will have little affect! You should look for a write-protect (aka 'Lock' or maybe a padlock symbol) switch on the device.

**If you are sure that none exists, consider re-programming the controller firmware

Reference :
Repair your USB flash drive
How to fix write protected disks
How to fix write protection errors on a USB stick
Removing the write-protection on a USB Memory Stick or SD Card - a beginner's guide

Compaq Presario CQ40 Won't Turn On

On startup, you may see a blank screen. If the diagnostic utilities detect a specific problem with hardware components, the fan turns on, but the screen remains blank. To help identify the cause of the problem, various LED lights on the keyboard blink a series of codes.

The diagnostic utilities use the LEDs near the Num Lock or Caps Lock keys to blink a series of error codes. At the end of the series the blinking stops. The pattern of blinks will occur any time you attempt to start the computer until the error is resolved.

Refer to: http://h10025.www1.hp.com