Check about-me¶

Overview¶

Collects and displays key system information: OS and kernel version, CPU configuration (physical, logical, and usable cores plus frequency), RAM, disk count, virtualization type, network interfaces, listening ports, systemd services and timers, cron jobs, installed packages, and user accounts. Optionally queries dmidecode for firmware and hardware details, and fetches the public IP address. This check is purely informational and never raises alerts. Requires root or sudo.

Important Notes:

Plugin execution may take up to 30 seconds, depending on the amount or type of installed software
The --dmidecode option requires sudo permissions
If psutil is not installed, some metrics (CPU frequency, network interfaces) will be unavailable

Data Collection:

Gathers hardware and OS data via psutil (if available), lsblk, stat, /proc/mounts, and various systemctl commands
Optionally runs dmidecode (via --dmidecode) to retrieve BIOS, chassis, base board, processor, and system boot information
Optionally fetches the public IP address from one or more configurable „what is my IP“ services (via --public-ip-url)
Lists all network interfaces with IPv4 addresses, listening TCP/UDP ports, non-default packages, non-default users, systemd services/mounts/automounts/timers, and cron jobs
Optionally guesses Icinga Director tags for automated host classification (via --tags)

Fact Sheet¶

Fact	Value
Check Plugin Download	https://github.com/Linuxfabrik/monitoring-plugins/tree/main/check-plugins/about-me
Nagios/Icinga Check Name	`check_about_me`
Check Interval Recommendation	Every day
Can be called without parameters	Yes
Runs on	Linux
Compiled for Windows	No
3rd Party Python modules	`psutil` (optional)

Help¶

usage: about-me [-h] [-V] [--dmidecode] [--insecure] [--no-proxy]
                [--public-ip-url PUBLIC_IP_URL] [--tags] [--timeout TIMEOUT]

Collects and displays key system information: OS and kernel version, CPU
configuration (physical, logical, and usable cores plus frequency), RAM, disk
count, virtualization type, network interfaces, listening ports, systemd
services and timers, cron jobs, installed packages, and user accounts.
Optionally queries dmidecode for firmware and hardware details, and fetches
the public IP address. This check is purely informational and never raises
alerts. Requires root or sudo.

options:
  -h, --help            show this help message and exit
  -V, --version         show program's version number and exit
  --dmidecode           Gather additional hardware information via the
                        `dmidecode` command, such as system components, serial
                        numbers, and BIOS revisions. Requires sudo
                        permissions.
  --insecure            This option explicitly allows insecure SSL
                        connections.
  --no-proxy            Do not use a proxy.
  --public-ip-url PUBLIC_IP_URL
                        One or more comma-separated URLs to "what is my ip"
                        online services for fetching the public IP address.
                        Example: `https://ipv4.icanhazip.com,https://ipecho.ne
                        t/plain,https://ipinfo.io/ip`. Default: None
  --tags                Guess a list of tags to apply in Icinga Director
                        (Linuxfabrik Basket config).
  --timeout TIMEOUT     Network timeout in seconds. Default: 2 (seconds)

Usage Examples¶

./about-me --dmidecode

Shortened output example:

server.example.com: Fedora Linux 42 (Workstation Edition) Kernel 6.16.4-200.fc42.x86_64 on Bare-Metal, Dell Inc. XPS 13 9350, Firmware: 1.20, SerNo: 12345678, Proc: Intel Core Ultra 7 258V, CPUs: 8/8/8 (phys/lcpu/onln), Current Speed: 3943 MHz, 30.9GiB/4.0GiB RAM (virtmem/max; reboot recommended), Disk nvme0n1 1.8T, UEFI boot, Display Server x11, tuned profile "throughput-performance", born 2024-03-20. About-me v2025090901

Hardware Info from `dmidecode`:
* BIOS: Dell Inc., Ver 1.13.0 (released 07/11/2025), ROM 64 MB
* SysInfo: Dell Inc. XPS 13 9350, SerNo 12345678, SKU n/a, Wake-up Type "Other",
  UUID 4c4c4544-005a-5110-804a-b8c04f593834
* Base Board: Type Motherboard Dell Inc. 0MMW13, SerNo /12345678/98765432/, Ver A01
* Chassis: Dell Inc., Type Notebook, SKU n/a, SerNo 12345678
  States: boot-up=Safe, pwr-supply=Safe, thermal=Safe, security=None
* Proc: Intel(R) Corporation, Ver Intel(R) Core(TM) Ultra 7 258V,
  Speed 4700 MHz/4800 MHz max., 8/8 Cores enabled, 8 Threads, Voltage 1.0 V
* System Boot: No errors detected

Interfaces (IPv4):
* ens10 192.0.2.6/32

Listening TCP/UDP Ports (ordered by port, proto, ip):
* 127.0.0.1:25/tcp4
* [::]:80/tcp6
* 0.0.0.0:111/tcp4
* [::]:111/tcp6
* 0.0.0.0:111/udp4
* [::]:111/udp6

Non-default Software (ordered by name):
name               ! version    ! from_repo                              ! installtime      
-------------------+------------+----------------------------------------+------------------
at                 ! 3.1.20     ! baseos                                 ! 2022-12-07 07:18 
bash-completion    ! 2.7        ! baseos                                 ! 2022-10-04 09:59 
bzip2              ! 1.0.6      ! baseos                                 ! 2022-10-04 11:40 
chrony             ! 4.2        ! baseos                                 ! 2022-12-07 07:17 
yum-utils          ! 4.0.21     ! baseos                                 ! 2023-11-28 03:21 
zstd               ! 1.4.4      ! appstream                              ! 2023-08-29 08:02 

Non-default Users:
user        ! pw ! uid  ! gid  ! comment                   ! home_dir           ! user_shell    
------------+----+------+------+---------------------------+--------------------+---------------
apache      ! x  ! 48   ! 48   ! Apache                    ! /usr/share/httpd   ! /sbin/nologin 
postfix     ! x  ! 89   ! 89   !                           ! /var/spool/postfix ! /sbin/nologin 
redis       ! x  ! 991  ! 986  ! Redis Database Server     ! /var/lib/redis     ! /sbin/nologin 

systemctl get-default:
* multi-user.target

systemctl list-unit-files --type=service --state=enabled:
* atd.service
* auditd.service
* autovt@.service
* chronyd.service

systemctl list-unit-files --type=mount --state=static --state=generated:
* -.mount
* boot-efi.mount
* dev-hugepages.mount

systemctl list-unit-files --type=automount --state=enabled --state=static:
* proc-sys-fs-binfmt_misc.automount

systemctl list-timers:
unit                               ! activates                      ! next                         
-----------------------------------+--------------------------------+------------------------------
fstrim.timer                       ! fstrim.service                 ! Mon 2024-04-15 01:07:55 CEST 
systemd-tmpfiles-clean.timer       ! systemd-tmpfiles-clean.service ! Thu 2024-04-11 04:35:37 CEST 
unbound-anchor.timer               ! unbound-anchor.service         ! Thu 2024-04-11 00:00:00 CEST 

crontab:
01 * * * * root run-parts /etc/cron.hourly
0 1 * * Sun root /usr/sbin/raid-check

States¶

Always returns OK.

Perfdata / Metrics¶

Name	Type	Description
cpu_freq	Number	Current CPU frequency in MHz. On Linux, reports the real-time value; on other platforms, usually the nominal fixed value.
cpu_logical	Number	Number of logical CPUs (physical cores multiplied by threads per core, i.e. Hyper-Threading).
cpu_physical	Number	Number of physical CPU cores.
cpu_usable	Number	Number of usable CPUs (may differ from total due to CPU affinity, cgroups, or processor groups).
disks	Number	Number of disks.
osversion	None	OS version as a comparable number, e.g. „Fedora 33“ becomes „33“, „CentOS 7.4.1708“ becomes „741708“.
ram	Bytes	Total RAM size.

Credits, License¶

Authors: Linuxfabrik GmbH, Zurich
License: The Unlicense, see LICENSE file.