DEV Community: Sharafat

How to find checksum of a Google Drive File

Sharafat — Sun, 23 Nov 2025 10:49:45 +0000

A checksum (hash) lets you verify a file has not been altered or corrupted. Common use: confirm a downloaded ISO matches the publisher’s SHA-256 hash.

1. Open Google Colab

Go to https://colab.research.google.com and create a new Python notebook.

2. Connect to Google Drive

Run:

from google.colab import drive
drive.mount('/content/drive')

Approve the auth prompt. Your Drive files appear under /content/drive/MyDrive/.

3. Locate the File Path

In the left sidebar (folder icon):

Navigate to the file.
Right‑click the file and choose "Copy path" (or manually note its path). Example path: /content/drive/MyDrive/DATA/iso/Win11_24H2_English_x64_Custom_Optimized.iso

4. Compute the SHA‑256 Checksum

Use sha256sum (installed by default in Colab):

!sha256sum /content/drive/MyDrive/DATA/iso/Win11_24H2_English_x64_Custom_Optimized.iso

Output format:

<sha256_hash>  <file_path>

5. Verify Against Known Hash

Compare the printed hash with the official one from the source website. They must match exactly. If not, the file may be incomplete or tampered with.

Common Issues

File not found: Confirm the path (case sensitive).
Large files: Hashing can take time; wait for completion.
Different algorithm needed: Replace with !md5sum or !sha1sum (only if required; SHA‑256 is stronger).

Setting up oracle database in Linux (podman container + vscode)

Sharafat — Wed, 22 Jan 2025 12:32:29 +0000

Installation

Mainly I will be focusing linux, but will work on mac as well with same commands.

For windows? You can download the installer from the official website and follow the instructions.

https://www.oracle.com/database/technologies/xe-downloads.html

Setup a container

Docker and podman are the two most popular containerization tools. I will be using podman for this, and I will recommend podman as well. Why? Maybe I will write a blog on this later.

Whatever, let's install podman! You can follow the official documentation for this. I guess most of the major linux distributions have podman in their official repositories.

Like, for Arch Linux:

sudo pacman -S podman

Pull the image

There are mainly two images available for free, full and lite.

To get the full image:

podman pull container-registry.oracle.com/database/free:latest

And to be honest, it's a huge image around 9.48 G. So, I will recommend the lite version. It may take upto 2 G.

podman pull container-registry.oracle.com/database/free:23.5.0.0-lite

Run the container

Now let's go ahead and actually run the container.

podman run -d -p 1521:1521 --name oracle-db container-registry.oracle.com/database/free:23.5.0.0-lite

Here, I have used the lite version of the image. You can use the full version as well. Just replace the image name.
And the port 1521 is the default port for Oracle Database. You can change it if you want.

Flag -d is used to run the container in the background.
Flag -p is used to map the host port to the container port.
Flag --name is used to give a name to the container. (Try to remember it!)

Set a password

Here I have used 1234 as the password. You can use whatever you want.

podman exec -it oracle-db ./setPassword.sh 1234

Connect to the database

You can use any database client to connect to the database. I will be using SQL*Plus.

podman exec -it oracle-db sqlplus

And then enter the following details:

Username: system
Password: 1234 (Or the one you set in the previous step!)

Stop the container

podman stop oracle-db

Start the container

podman start oracle-db

You may need to start the container if you have restarted your system!

Misc

Port address

To get your outgoing forwarded port from podman, use the following,

podman port oracle-db

Integration

VSCODE

It would be weird if we have to use terminal everytime we want to access our database, right?
Let's use vscode. Simply install the following extension,

https://marketplace.visualstudio.com/items?itemName=Oracle.sql-developer

Or, Launch VS Code Quick Open (Ctrl+P), paste the following command, and press enter.

ext install Oracle.sql-developer

The size of this extension is more than 300 M, so it'll take a bit of time.

Now on our left/ right toolbar, you will find a icon, and maybe try to add a new connection? You will asked to fill up a form.
For the port number try to use the one you got from podman port oracle-db.
For the username, use system.
And for the password, use the one you set in the previous steps.
For the service name, it should be FREE. Or you can use the following code in sqlplus to get the service name,

SELECT VALUE 
FROM V$PARAMETER 
WHERE NAME = 'service_names';

And you are good to go!

Running MySQl in Linux (with/ without podman container with phpmyadmin)

Sharafat — Wed, 22 Jan 2025 12:30:08 +0000

My SQL

MySQL is a RDBMS software which use SQL like syntax to manage databases. Nowadays most of the major linux distributions come with maria db preinstalled, which is an open source drop in replace ment for MySQL. I’ll be writing about some ways to install MySQL in linux based operating systems,

XAMPP

Xampp is a popular tool which is an open source cross-platform web server solution stack package developed by Apache friends. It can be installed via the official website’s installer. Here a .run file will be downloaded which can be installed by executing from a terminal. But it is not recommended to install in this way.
The most recommended way is to search for a similar package in distros native package manager. For example, in Arch Linux the package is available through AUR (Arch User Repository). Here’s the git-clone URL,

https://aur.archlinux.org/packages/xampp

To install it, we can use a AUR wrapper like yay. To do so, use the following command to query and install the latest version of xampp.

yay xampp

After installing open the app, head over to the second tab and start database and web server. Web UI will be available under localhost.

Podman Container

One another good way to install MySQL is to use a podman or docker container. I personally prefer podman so I will be writing about it. Installing a container running only MySQL is pretty much easy. We just have to grub the image and run it in a container. It’s volume will be created automatically. Or if we also want to include a phpmyadmin web app to manage our image then we actually have to use a pod to contain two different containers.

MySQL image

To setting up MySQL image, we can pull it from dockerhub. The command will be like,

podman pull mysql

then, we can start and run our image with the following command,

podman run -d -p 3306:3306 -e MYSQL_ROOT_PASSWORD=tree --name mysql-db mysql:latest

Here our root password is defined as tree by the environement variable MYSQL_ROOT_PASSWORD.
And if we try to do list running process we can execute,

podman ps

It will see our image up and running. Now let’s actually enter to our server!

podman exec -it mysql-db mysql -u root -p

Let’s run a command to verify,

show databases;

It’ll list all databases.
Now with localhost:3306 you can access this database from mysql workbench or other clients.

Phpmyadmin image

Phpmyadmin is a web UI for managing MySQL databases. Let’s pull it first,

podman pull phpmyadmin

Now if run this image we won’t be able to access another image (MySQL) because there’s no connection in between them. So we will be using podman pod. Let’s create a podman pod,

podman pod create --name mysql -p 8080:8080 3306:3306

If we have previously created an image as per this guide and that is up and running, try the follwing command to stop and delete,

podman stop mysql-db && podman rm mysql-db

Now let’s start our mysql server under this pod,

podman run -d -e MYSQL_ROOT_PASSWORD=tree --pod mysql --name mysql-db mysql:latest

And finally let’s open our phpmyadmin with this pod,

podman run --name phpmyadmin -e PMA_ARBITRARY=1 -d --pod mysql phpmyadmin

It will be availabe under port 8080, as like we defined earlier. So let’s head over to,

http://localhost:8080/

Here, our,

Server = localhost:3306
Username = root
Password = tree
This can be also done graphically with the help of `podman desktop`.

Docker

Pull the image from the docker hub

docker pull mysql

or, using podman?

podman pull docker.io/library/mysql

Now, let’s create our first container from the mysql image. Here is the command we will use:

docker run --name test-mysql -p 3306:3306 -e MYSQL_ROOT_PASSWORD=tree -d mysql

run: creates a new container or starts an existing one

--name CONTAINER_NAME: gives the container a name. The name should be readable and short. In our case, the name is test-mysql.

-e ENV_VARIABLE=value: the -e tag creates an environment variable that will be accessible within the container. It is crucial to set MYSQL_ROOT_PASSWORD so that we can run SQL commands later from the container. Make sure to store your strong password somewhere safe (not your brain).

-d: short for detached, the -d tag makes the container run in the background. If you remove this tag, the command will keep printing logs until the container stops.

image_name: the final argument is the image name the container will be built from. In this case, our image is mysql.

-p HOST_PORT:CONTAINER_PORT: the -p tag maps a port from the host machine to the container. In this case, we are mapping port 3306 from the host to the container. This is the default port for MySQL.

If the command returns a long string of gibberish (the container ID), it means the container has started. You can check its status with docker ps:

To access the terminal inside your container, you can use the following command:

docker exec -it container_name bash

And then to login to mysql:

mysql -u root -p

Troubleshooting

https://stackoverflow.com/questions/41645309/mysql-error-access-denied-for-user-rootlocalhost

disable Bluetooth at startup in TLP

Sharafat — Sun, 07 May 2023 15:40:33 +0000

TLP

From the project page:

TLP is a feature-rich command line utility for Linux, saving laptop battery power without the need to delve deeper into technical details.
TLP’s default settings are already optimized for battery life and implement Powertop’s recommendations out of the box. So you may just install and forget it.
Nevertheless TLP is highly customizable to fulfil your specific requirements.

Steps

To disable Bluetooth at startup, open the following file in your preferred text editor (root privilege will be required),

/etc/tlp.conf

For example to use nano text editor, your command will be, sudo nanao /etc/tlp.conf.

Then change,

RESTORE_DEVICE_STATE_ON_STARTUP=0

RESTORE_DEVICE_STATE_ON_STARTUP=1

And, also use the following line,

DEVICES_TO_DISABLE_ON_STARTUP="bluetooth"

Don't forget to remove the '#' from the beginning of a line (removing comments).

Example layout

Here is a basic example of my config,

# Restore radio device state (Bluetooth, WiFi, WWAN) from previous shutdown
# on system startup: 0=disable, 1=enable.
# Note: the parameters DEVICES_TO_DISABLE/ENABLE_ON_STARTUP/SHUTDOWN below
# are ignored when this is enabled.
# Default: 0

RESTORE_DEVICE_STATE_ON_STARTUP=1

# Radio devices to disable on startup: bluetooth, nfc, wifi, wwan.
# Separate multiple devices with spaces.
# Default: <none>

#DEVICES_TO_DISABLE_ON_STARTUP="bluetooth nfc wifi wwan"
DEVICES_TO_DISABLE_ON_STARTUP="bluetooth nfc wwan"

Here besides bluetooth, I've also disabled nfc and wwan.

References

Manjaro forum - Bluetooth Turns On Automatically After Reboot!