The Wiert Corner – irregular stream of stuff

Jeroen W. Pluimers on .NET, C#, Delphi, databases, and personal interests

  • My badges

    Mastodon

  • Twitter Updates

  • My Flickr Stream

    20140508-Delphi-2007--Project-Options--Cannot-Edit-Application-Title-HelpFile-Icon-Theming20140430-Fiddler-Filter-Actions-Button-Run-Filterset-now20140424-VMware-Fusion-6.0.3.-no-reclaimable
    More Photos

  • Pages

  • All categories

  • Enter your email address to subscribe to this blog and receive notifications of new posts by email.

    Join 1,830 other subscribers

Archive for the ‘Linux’ Category

« Previous Entries
Next Entries »

zabbix on Windows: check the configuration before restarting the Zabbix Agent service

Posted by jpluimers on 2019/09/27

If the Zabbix configuration on Windows (especially mismatches in C:\zabbix\zabbix.agentd.conf.d), then the Zabbix Agent will not start at all:

C:\zabbix\bin\win64>zabbix_agentd.exe --start
zabbix_agentd.exe [4711]: ERROR: cannot start service [Zabbix Agent]: [0x0000041D] The service did not respond to the start or control request in a timely fashion.

This is how to check it before starting the service:

C:\zabbix\bin\win64\zabbix_agentd.exe --config C:\zabbix_agentd.conf
zabbix_agentd.exe [43]: ERROR: cannot add user parameter "MyDuplicate[*],PowerShell.exe -File C:\zabbix\UniquePowerShellScript.ps1 "$1"": key "MyDuplicate" already exists

The problem is that in the C:\zabbix\zabbix.agent.conf.d directory, two files had a similar config:

UserParameter=MyDuplicate[*],PowerShell.exe -File C:\zabbix\FirstPowerShellScript.ps1 "$1"
UserParameter=MyDuplicate[*],PowerShell.exe -File C:\zabbix\SecondPowerShellScript.ps1 "$1"

The problem is that the first part of UserParameter (before the [*])  is a key which needs to be unique over all configuration files.

If everything is fine, you will see this:

C:\zabbix\bin\win64\zabbix_agentd.exe --config C:\zabbix_agentd.conf
zabbix_agentd.exe [1581]: use foreground option to run Zabbix agent as console application

If you need to manually start Zabbix as a service, then perform this (the first step is not needed if the service has already been stopped):

C:\zabbix\bin\win64>zabbix_agentd.exe --stop
zabbix_agentd.exe [1642]: service [Zabbix Agent] stopped successfully

C:\zabbix\bin\win64>zabbix_agentd.exe --start
zabbix_agentd.exe [1642]: service [Zabbix Agent] started successfully

–jeroen

Posted in *nix, Linux, Monitoring, Power User, Windows, Zabbix | Leave a Comment »

Eigenes DynDNS mit Bind und Apache – CupRacer.de

Posted by jpluimers on 2019/09/16

Dieser Artikel beschreibt, wie man einen eigenen Mechanismus für DNS-Updates als DynDNS-Alternative aufbaut.

Translated:

This article describes how you can create your own mechanism for DNS-updates as alternative for DynDNS.

Interesting read: [WayBack] Eigenes DynDNS mit Bind und Apache – CupRacer.de

Edit

The above post disappeared, but this one (which adds calling the DynDNS server from a Fritz!Box) is still up: [WayBack] Eigener DynDNS mit Bind, Apache und PHP | onderka.com with an update at [WayBack] Eigener DynDNS mit dnsmasq, Apache und PHP | onderka.com.

Source code for both:

Related and background reading:

–jeroen

Posted in *nix, bind-named, Linux, openSuSE, Power User, SuSE Linux, Tumbleweed | Leave a Comment »

Signal messaging downloads

Posted by jpluimers on 2019/08/23

I forgot about the announcement that Signal had also become available on the Desktop, but it is via [WayBack] https://signal.org/download/:

  • Mac
  • Windows
  • Debian based x64 Linux:

$ curl -s https://updates.signal.org/desktop/apt/keys.asc | sudo apt-key add -
$ echo "deb [arch=amd64] https://updates.signal.org/desktop/apt xenial main" | sudo tee -a /etc/apt/sources.list.d/signal-xenial.list
$ sudo apt update && sudo apt install signal-desktop

I like the mix of echo and tee to update the [WayBack] /etc/apt/sources.list.d folder with the signal-xenial.list file.

These links will always give you the latest download filename:

The files you get there will be relative to the path https://updates.signal.org/desktop/ so will be similar to:

You can get the sources at https://github.com/WhisperSystems/Signal-Desktop/releases

Via:

–jeroen

Posted in *nix, Android Devices, Apple, Debian, iMac, iOS, iPhone, Linux, Mac, Mac OS X / OS X / MacOS, MacBook, MacBook Retina, MacBook-Air, MacBook-Pro, MacMini, macOS 10.12 Sierra, Power User, Windows | Leave a Comment »

Introduction to Snapshots/Rollback with Snapper | ActiveDoc

Posted by jpluimers on 2019/07/01

The snapper documentation itself is big and hard to grasp at once, so start here for a few examples on how to get going, or how to assess your current configuration:

For a very good snapper introduction seems to be gone, but was present in the OpenSuSE documentation archive circa version 13.2 at [WayBack] Chapter 4. Snapshots/Rollback with Snapper | ActiveDoc which I’ve quoted below.

Between that version and LEAP, the retention got moved from “timeline” based to “number” based. More on that in these links:

Man pages:

Introduction

4.1.1 snapshots and Disk Space #

When a snapshot is created, both the snapshot and the original point to the same blocks in the file system. So, initially a snapshot does not occupy additional disk space. If data in the original file system is modified, changed data blocks are copied while the old data blocks are kept for the snapshot. Therefore, a snapshot occupies the same amount of space as the data modified. So, over time, the amount of space a snapshot allocates, constantly grows. As a consequence, deleting files from a Btrfs file system containing snapshots may not free disk space!

Note: Snapshot Location

Snapshots always reside on the same partition or subvolume that has been snapshotted. It is not possible to store snapshots on a different partition or subvolume.

As a result, partitions containing snapshots need to be larger than “normal” partitions. The exact amount strongly depends on the number of snapshots you keep and the amount of data modifications. As a rule of thumb you should consider using twice the size than you normally would.

Tip: Freeing space / Disk Usage

In order to free space on a Btrfs partition containing snapshots you need to delete unneeded snapshots rather than files. Older snapshots occupy more space than recent ones.

Since the df does not show the correct disk usage on Btrfs file systems, you need to use the command btrfs filesystem df MOUNT_POINT. Displaying the amount of disk space a snapshot allocates is currently not supported by the Btrfs tools.

–jeroen

Posted in *nix, Linux, openSuSE, Power User, SuSE Linux, Tumbleweed | Leave a Comment »

ls colour codes on OpenSuSE tumbleweed when accessed from Mac OS X ssh

Posted by jpluimers on 2019/06/07

`ls` colour codes

`ls` colour codes

I got confused as I thought red text would mean an error.

But they’re not: greenish yellow on a read background means error (a symbolic link to a place that’s no longer there).

It’s the output of https://github.com/gkotian/gautam_linux/blob/master/scripts/colours.sh as the one at

Actually the script is here https://raw.githubusercontent.com/gkotian/gautam_linux/master/scripts/colours.sh as the one at [WayBack] command line – What do the different colors mean in the terminal? – Ask Ubuntu failed with errors like this one:

-bash: *.xbm: bad substitution

The full script output is below.

Since various terminals have a different mapping from colours in the ANSI escape code colour table, I used the standard HTML colours using (which slightly differs from the Terminal.app screenshot on the right):

References:

Note that the shell on Mac OS X uses a different way of configuring colours CLICOLOR as described in [WayBack] settings – CLICOLOR and LS_COLORS in bash – Unix & Linux Stack Exchange. I might cover that another day.

Script output:

Read the rest of this entry »

Posted in *nix, *nix-tools, ANSI escape code, bash, CSS, Development, Encoding, HTML, HTML5, Linux, openSuSE, Power User, Software Development, SuSE Linux, Tumbleweed, Web Development | Leave a Comment »

When your btrfs partition is damaged.

Posted by jpluimers on 2019/05/27

A while ago, I somehow had a damaged btrfs partition that I found out after the virtualisation host without reason decided to reboot.

I’m not sure what caused that (by now the machine has been retired as it was already getting a bit old), but btrfs was panicking shortly after boot, so the VM as is was unusable.

In the end I had to:

  1. Boot from a Tumbleweed Rescue DVD (download Rescue CD – x86_64 from [WayBack] openSUSE:Tumbleweed installation – openSUSE)
  2. Add a fresh backup hard disk in read-write mote
  3. Mount the old one in read-only mode
  4. rsync -avloz over as much as I could
  5. Restore the VM from a backup
  6. Attach the backup hard disk
  7. Diff what I missed (only a few bits in the /etc tree and my home directory for which I hadn’t yet pushed the git repositories).

These didn’t work, but might work for others: [WayBack] SDB:BTRFS – openSUSE – How to repair a broken/unmountable btrfs filesystem

–jeroen

Posted in *nix, btrfs, File-Systems, Linux, openSuSE, Power User, SuSE Linux, Tumbleweed | Leave a Comment »

systemd – How to clear journalctl – Unix & Linux Stack Exchange

Posted by jpluimers on 2019/05/24

Some tips on pruning entries from the systemd journal:

For stock opensuse, this is also relevant, as it seems to allow indefinite growth: [WayBack] systemd – journald Settings likey need your attention

You can view disk usage with this command:

journalctl --disk-usage

–jeroen

Posted in *nix, Linux, Power User, systemd | Leave a Comment »

Reset Linux Desktop To Default Settings With A Single Command – OSTechNix

Posted by jpluimers on 2019/05/16

To reset Ubuntu Unity or any other Linux desktop with GNOME/MATE DEs to its default settings, run:

dconf reset -f /

Source: [WayBack] Reset Linux Desktop To Default Settings With A Single Command – OSTechNix

I need to check if it works on OpenSuSE with XFCE as there the dconf command is installed, but I still have a default desktop (mainly because most of the work I do is using a terminal over ssh).

–jeroen

via: [Archive.is] Never thought about dconf reset… Joe C. Hecht – Google+

Posted in *nix, *nix-tools, Linux, Power User, X11 | Leave a Comment »

command line – How to access a usb flash drive from the terminal? – Ask Ubuntu

Posted by jpluimers on 2019/05/13

Based on [WayBack] command line – How to access a usb flash drive from the terminal? – Ask Ubuntu

Figure out the device:

  • lsblk
  • sudo blkid
  • sudo fdisk -l

Mount the device (assuming it is /dev/sdb1):

  • sudo mount /dev/sdb1 /media/usb
  • pmount /dev/sdb1
  • udisksctl mount -b /dev/sdb1

Unmounting and eject is in [WayBack] Linux (Ubuntu): safely remove USB flash disk via command line – Stack Overflow

–jeroen

Posted in *nix, *nix-tools, Linux, Power User | Leave a Comment »

How to Find Out Top Directories and Files (Disk Space) in Linux

Posted by jpluimers on 2019/04/26

Cool list of ls , sort and find to get the largest files, directories: [WayBack] How to Find Out Top Directories and Files (Disk Space) in Linux.

–jeroen

Posted in *nix, *nix-tools, Linux, Power User | Leave a Comment »

« Previous Entries
Next Entries »