Thursday, September 05, 2024

Debian 12.7 Release

Debian 12.7 Release

New release of Debian 12.7 at the end of August 2024. It says there are some security improvement.

Do I need to reinstall to upgrade? No, just update will do.

Do I need to dist-upgrade? No, just update will do.

You can use apt-get, aptitude or nala or any other debian software package manager.

eg.
$ sudo apt update && sudo apt upgrade

Check your version:

$ cat /etc/debian_version
12.7

Thursday, August 29, 2024

How to enable secure2u in Maybank MAE mobile app

How to enable secure2u in Maybank MAE mobile App


Maybank has 2 mobile app

The older Maybank2u app and newer MAE. MAE has eWallet and some other features. Old Maybank2u app will be retired.

What is Secure2u?

Secure2u is the security feature to replace the 6 digits OTP (One Time Password) from SMS. It send notification through the app, and approve with the Maybank2u app or MAE app. Secure2u will be the preferred method for Maybank2u online transactions.

Almost with no choice, you will need to install a Maybank online app. Maybank still keep the SMS OTP TAC as an option, not sure when it last.

Refer https://www.maybank2u.com.my/maybank2u/malaysia/en/personal/services/digital_banking/secure2u.page

Install MAE

Note: You need to choose a 6 digits PIN for MAE eWallet transaction.

If you already have Maybank2u app, you can just activate secure2u in Maybank2u app.

Install MAE for the first time, you need to create a 6 digits PIN. You may need to create a new MAE account for eWallet, or you can use your existing account.

Note: How to change MAE eWallet limit?

Reference. https://www.maybank2u.com.my/iwov-resources/pdf/upload/maeapp/MAEApp_FAQ_202009.pdf

How to enable Secure2u?

From quick access menu, click the secure2u icon, and follow the instructions.

Conclusion

Things to take note:

1. The transaction approval time is short. I normally need to login the MAE (or Maybank2u) app, get ready before I preform online transaction. I experience time out issues, if do not get it ready.

2. MAE doesn't logout automatically when it was not used. You need to secure your mobile phone with your passcode. (Hope Maybank can fix this in the future)

Note: MAE seems loading and perform quite slow.

Theoritically it is more secure to use the mobile app for online transactions compare to the SMS OTP. You must secure your mobile phone and the online banking app.

Thursday, August 22, 2024

ADB Enable "Drawing over other apps"

ADB Enable "Drawing over other apps"

I use ADB for these few things for now:

1. transfer file
$ adb pull /sdcard/Pictures/screenshot1.png . # download a picture from Android device to local
$ adb push screenshot2.jpg /sdcard/Pictures/. # upload to Android device

2. install apk app
$ adb install examples.apk # install apk app from local to the Android device

3. screen capture / screenshot
$ adb shell screenshot -p /sdcard/Pictures/screenshot1.png
Note: -p for png format.

4. Enable "Drawing over other app"
TimeNetSpeed app can display Internet download speed over other application. I was not able to enable it on Android TV. The error is: need "Drawing over other app" permission, but there is no such option to enable the permission.

$ adb shell appops set visnkmr.apps.timenetspeed SYSTEM_ALERT_WINDOW allow

Note: To disable $ appops set visnkmr.apps.timenetspeed SYSTEM_ALERT_WINDOW deny

Thursday, August 15, 2024

Why I use Debian Linux

Why I use Debian Linux

There are so many Linux distributions, you can choose the one which suits you most.

I have tried so many Linux distributions before, from Red Hat to Ubuntu. Finally I settled down with Debian. Ubuntu is based on Debian, Raspberry Pi Desktop is based on Debian, the Chrome OS Linux VM is a Debian.

I am already getting used to Debian. Debian has a lot of pre-compiled packages, available in many architecture platforms like x86 32 bits, 64 bits and ARM. Even Docker provides an easy way to install on Debian.

The installation process is easy as well. For commercial usage, user may choose Red Hat or Ubuntu, but for beginners, I will recommend Debian.

Thursday, August 08, 2024

I Have Lost Track With Arduino

I Have Lost Track With Arduino

My friend bought a ESP32 microcontroller board for MYR10 from Shopee. ESP32 microcontroller is a dirt cheap controller from the Shanghai company Espressif.

Users choose ESP32 for its low price, good support (especially software) and with Wifi (and bluetooth).

There are many versions of ESP32, like C3, C6 etc. The one that I am most interested in is ESP32-S2. This is a microcontroller with a duo core, but in most cases, you don't need a duo core or are unable to use the duo core.

Even Arduino has a board with ESP32-S2, Arduino nano ESP32. This board came with 16Mb storage, did I read it clearly? Most arduino boards came with a few hundred kilobytes. With Arduino support, you can program with micropython as well. For those who are willing to spend a little more, consider this board for a start.

Thursday, August 01, 2024

Connect Alexa Echo As External Speaker From Linux LXDE

Connect Alexa Echo As External Speaker From Linux LXDE

I have this old E5200 Petium Duo Core machine, installed with Raspberry Pi Desktop. This machine doesn't came with bluetooth, so I just bought a cheap bluetooth dongle (Essanger bluetooth 5.1), which I don't even know will work or not, luckily it works.

These are the simple steps to connect the Alexa Echo as an external speaker through bluetooth:

1. mobile > Alexa app > Devices > [x] Echo. Then you notice the LED of the speaker is blinking.
Note: Connect the bluetooth device (the Echo speaker) from the machine.

2. RPi Desktop > Bluetooth icon (LXDE panel)

3. After connected, right clock at the sound icon, select the specific speaker.

That's all.

Thursday, July 25, 2024

JTKE LTE 4G USB Modem Simple Review

JTKE LTE 4G USB Modem Simple Review

I am using my phone as an Internet modem, and it is overheating.

So I took out the JTKE LTE 4G USB modem to connect to the Internet. I bought this modem at quite a cheap price, yes it does not have 5G, maybe that is the reason it is cheap.

This is not just a modem, it can be a wifi router as well. It uses the normal SIM card, not the nano or micro SIM card. I am not sure it is called the mini SIM card. Is not the name card size SIM card as well. A lot of the people may not know or have forgotten, the very first version of the SIM card is actually (name) card size SIM card.

Pro. It is working as it should be. Cheap, easy to setup. USB modem and wifi router.

Cons. Wifi is always working, but the USB modem only working for Windows 11 only, other OS may need more effort to get it to work.

Configuration

The preset SSID (hotspot name) and password is printed on the USB modem. Another admin (and password) is use to change the SSID and password of the modem. To change the SSID, password or admin password, just use a browser access to http://192.168.100.1/

macOS (Ventura 13)

Wifi access is no problem. I have issues getting it working as a USB modem on macOS. Since nothing was written on the modem or user manual, I am not sure what chipset the modem is using. I guess it is Huawei, trying to install the Huawei driver, but either unable to install on the macOS Ventura properly, or it is not the correct driver.

Later I found it was stated on the online merchant website, it is using a Qualcomm 9600 chipset. I can not confirm, as I can't find the driver for macOS.

Windows 11

It just plug and play, working ok on Windows 11 without any configuration. It Seems like Windows is still the best support for third party hardware.

Chrome OS 2024

It can detect the modem, but is unable to connect to the Internet.

Debain 12 Linux

Haven't tested yet.

Tuesday, July 23, 2024

Is it a Good Time To Use an Alternative Than Windows Solution?

Is it a Good Time To Use an Alternative Than Windows Solution?

CrowdStrike impact

As a software developer, I always meet people who only use Microsoft Windows solutions, even though Windows is not stable to work as a server (their solution is to reboot 1-2 times every week). Still these people choose Windows as their software solution, for 2 reasons, 1. They only know Windows. 2. An IT manager will not be fired for choosing the Windows solution.

I thought Windows NT should be quite stable after being developed for many years, until the 'CrowdStrike BSOD' case happened (on 19 July 2024). It caused a lot of flights to be delayed, the USJ (Universal Studio Osaka, Japan) payment system was not working etc. etc.

CrowdStrike is an antivirus and security platform. CrowdStrike pushed a software update last Friday that causes BSOD (Blue Screen of Death), the Windows system goes into a non-stop booting loop.

An antivirus or security software shouldn't cause a kernel error or a system error. CrowdStrike is supposed to protect the system, not the other way round. That came into my mind, is it a good time for the IT solution people to rethink, should we use an alternative solution other than Windows, for example Linux. (Ok, I know CrowdStrike crash Linux before as well)

Linus Torvald is cautiously accepting Rust to be used in Linux kernel development, one of the concerns is the stability of the Linux kernel. Think twice again, it is less likely that an IT manager will choose an alternative solution than Windows. Why? For the same old reason, an IT manager will not be fired for choosing the Windows solution.

I would like to see more varieties in software solutions. Why? The Windows BSOD is a good reason.

Friday, July 19, 2024

A Quick Solution To Microsoft BSOD Today (CrowdStrike)

A Quick Solution To Microsoft BSOD Today (CrowdStrike)

1. Boot Windows in safe mode.
2. del C:\Windows\System32\drivers\CrowdStrike\C-00000291*.sys
3. reboot

Thursday, July 18, 2024

QEMU with command line

QEMU with command line


Introduction

QEMU is Quick emulator. This tutorial works on Qemu 9.0.1.

Installation

Debian: $ apt install qemu
Homebrew: $ brew install qemu
Linuxbrew: $ brew install qemu

Using qemu

Create image:

$ qemu-img create -f qcow2 alpine_disk.qcow2 12G
$ ls alpine_disk.qcow2
⇒ only created a 192k image file, even though it was stated to be 12G. The file will grow if it needs more space.

Launch QEMU

$ qemu-system-x86_64 \
-enable-kvm -m 2G -smp 1 \
-hda alpine_disk.qcow2 \
-boot d -cdrom alpine_linux.iso \
-netdev user,id=net0,net=192.168.0.0/24 \
-device virtio-net-pci,netdev=net0 \
-vga virtio \
-device AC97

## if no AC97 audio, just remove it
## -enable-kvm, use kernel kvm virtualization
## -cpu host, if you have this error warning: host doesn't support requested feature: CPUID.80000001H:ECX.svm [bit 2]

Hardware virtualization

Modern CPUs have hardware virtualization. Qemu performs much faster with hardware virtualization. For macOS, no KVM, use -machine type=q35,accel=hvf, for macOS virtualization framework.

## Linux -enable-kvm
## macOS -machine type=q35,accel=hvf

Install Alpine Linux

Choose Alpine Linux as an example, because it is small and simple.

Installation:

1. keymap (us,us)
2. network setting use default or [dhcp]
3. timezone [Singapore]
4. mirror [1]
5. add in new user (other than root) with username and password
6. Which disk to use [none]? sda ## depends on your system
7. How would you like to install it (sys, data, lvm…)? sys
8. Erase disk? y

Alpine Linux on Qemu

After the OS installation:

$ qemu-system-x86_64 \
-m 1G -smp 1 \
-hda alpine_disk.qcow2 \
-netdev user,id=net0,net=192.168.0.0/24 \
-device virtio-net-pci,netdev=net0 \
-nodisplay

Qemu display
## -nographic, not creating another window
## -vga virtio -display default, shows progress and login prompt

Reset terminal

If you need to reset terminal for word wrap.
$ reset
$ tput smam

Ssh from host to guest OS

Using ,hostfwd=tcp::2222-:22

## map host os port 2222 to guest os port 22
$ qemu-system-x86_64 \

-netdev user,id=net0,net=192.168.0.0/24,hostfwd=tcp::2222-:22


$ ssh user@localhost -p 2222

Thursday, July 11, 2024

Easy Install Docker On Debian 64 bit

Easy Install Docker On Debian 64 bit

This is using command line.

Easy way (Debian)

I found an easy way to install Docker on Debian 64 bit (arm64 and amd64). I just tested on Debian 12 Bookworm, didn't try on Arm platform. If you fail, may be Docker didn't provide the binary of your platform, for example Debian 32 bit.

$ apt update
$ apt upgrade
## need curl and apt-utils
$ curl -fsSL test.docker.com -o get-docker.sh && sh get-docker.sh
$ docker -v
⇒ version 27

Test Docker
$ sudo docker run hello-world ## docker need root
⇒ Hello from Docker!
If you see the Hello message, it is working.

macOS (Homebrew + Docker Desktop)

Homebrew only install the docker (client), you need a Docker daemon). Docker Desktop can start the Docker daemon. Docker Desktop is available for download, available in macOS, Windows and Linux platform.

$ brew install docker docker-compose
$ sudo docker run hello-world ## to test

You can use Colima (lima) + qemu to replace the Docker Desktop, it works.

Thursday, July 04, 2024

Unix Compress Tips (gz xz etc)

Unix Compress Tips (gz xz etc)

Another incomplete jumpstart tutorial or tips for unix compression.

There are a few types of unix compress format eg. gz, bz2, what are the differences? Z is very old unix compress, probable no one is using it now. The gz and bz2 (bzip2) is quite common for compressing text base file, eg. source code. The gz and bz2 format existed and commonly use for a long time (80s, 90s to...).

The xz is newer, it has a better compression ratio, but it also takes more resources (cpu and ram), normally used to compress large binary files. The Zip is very common in Windows systems.

The is how to compress 2 files, dummy and hello.txt:

## compress found in debian ncompress package
## '-c' to create archive, '-O' to output to stdout
## '-cO' same with '-c --to-stdout'
## '-cO' same with '-cf -'
$ tar -cO dummy hello.txt | compress -c > hello.tar.Z
⇒ hello.tar.Z

## gz, -z for gz
$ tar -czf hello.tar.gz dummy hello.txt

## bzip2, -j (capital J)
$ tar -cjf hello.tar.bz2 dummy hello.txt
⇒ hello.tar.bz2 in gzip2 format

## xz, -J
$ tar -cJf hello.tar.xz dummy hello.txt
⇒ hello.tar.xz in xz format

## zip
$ zip -r hello.zip dummy hello.txt

updating: dummy (stored 0%)
updating: hello.txt (deflated 49%)

Hope you enjoy these quick tips.

Thursday, June 27, 2024

Is Intel N100 Mini PC a Good Buy?

Is Intel N100 mini PC a good buy?

It depends on what you want to do with it. It should be good for general usage, but not for gaming.

The Intel N100 CPU was released 2023 January. It is using Alder Lake-N, base on Alder Lake but with some modification.

The Alder Lake family (aka Intel 7) is one of the latest architecture. The Alder Lake-N is the ultra low power consumption CPU, eg. N100 at 6 watts only. The Alder Lake-N has 4 E-cores (Efficient core) and no P-core (Performance care). (that’s why is cheaper?)

Integrated graphic is Iris Xe. Iris Xe is a high GPU, but it is so new that you might not able to find a proper driver for it.

N5105 using Jasper Lake architecture, which is older compare to N100. the integrate graphic cards perform comparable to the Iris Xe. Intel N5105 has Intel VT-x for virtualization. Both Intel N100 and N5105 has VT-x.

If you are working with virtualization software examples virtual box, Qemu, you might want to use the N5105, but Docker on Linux, doesn’t make use of the VT-x technology. For Docker users might want to consider using Intel N100.

Anyway talk is just theory. I am waiting for my N100 machine to delivery. Then I can do testing for reference.

Friday, June 21, 2024

Docker is good for ...

Docker is good for testing and production

Docker is a lightweight container, is small, fast and secure. Docker is easy to use (should be easy to setup as well).

Docker is good for testing and deploying. For sample, you want to test your application on Red Hat Linux. You don't want to install another machine, so your test it on Docker. For sure I prefer to test it on Alpine than Red Hat.