Monthly Archives: April 2023

Compressing mysqldump with pipe: MySQL

 in Bash / GNU/Linux  tagged compress / gzip / mysql / mysqldump by

When working with MySQL databases, it’s common to create backups of the database using the mysqldump utility. However, these backups can often take up a significant amount of disk space, especially for large databases. One way to reduce the size of these backups is to compress them using a compression algorithm. In this post, we will explore how to compress a mysqldump using a pipe.

First, let’s review the basic syntax for creating a mysqldump:

mysqldump -u [username] -p [database_name] > [backup_file].sql

This command will create a plain-text backup file of the specified database, which can then be restored using the mysql command. However, this backup file can be quite large, especially for large databases.

To compress the backup file, we can use a pipe to redirect the output of the mysqldump command to a compression utility. One common compression utility is gzip, which uses the gzip algorithm to compress files. Here’s how we can use gzip to compress the mysqldump:

mysqldump -u [username] -p [database_name] | gzip > [backup_file].sql.gz

In this command, we use the | symbol to pipe the output of the mysqldump command to the gzip command. The > symbol is then used to redirect the compressed output to a file with a .sql.gz extension.

The resulting backup file will be compressed using the gzip algorithm, which typically results in significant reduction in file size. To restore the backup, we can use the following command:

gunzip < [backup_file].sql.gz | mysql -u [username] -p [database_name]

In this command, we use the gunzip command to decompress the compressed backup file, which is then piped to the mysql command to restore the database.

In conclusion, compressing a mysqldump using a pipe is a simple and effective way to reduce the size of backup files. By using a compression utility such as gzip, we can significantly reduce the amount of disk space required to store backups, while still being able to restore the database using standard MySQL commands.

Cloudflare API DNS Update

 in Applications / Bash / Firewall / GNU/Linux / HowTos  tagged api / cloudflare / DNS / update DNS record / what is my ip by

Cloudflare is a content delivery network (CDN) that provides a wide range of services, including domain name system (DNS) management. The Cloudflare API allows developers to programmatically manage DNS records, making it possible to automate updating DNS records. This blog post will explain how to use the Cloudflare API to update a DNS record.

Log in to Cloudflare and get your Global API Key

First, log in to your Cloudflare account and obtain your Global API Key. You can obtain your Global API Key by navigating to the URL: https://dash.cloudflare.com/profile/api-tokens. Once logged in, you should see a section called “API Tokens.” Click on the “View” button to see your Global API Key.

Find the Zone ID

The next step is to find the Zone ID of the domain you want to update. You can find the Zone ID by following the instructions provided in the Cloudflare documentation: https://developers.cloudflare.com/fundamentals/get-started/basic-tasks/find-account-and-zone-ids/.

  1. Click on the domain you want to manage.
  2. In the left-hand sidebar, click on “Overview.”
  3. Scroll to the “API” section and click “Get your API key.”
  4. Click on the “View” button next to the Global API Key.
  5. Copy the key and keep it somewhere safe.

Get the DNS Record Identifiers

Once you have obtained the Zone ID, you can use it to get the identifiers for the DNS records associated with that domain. You can do this by making a GET request to the Cloudflare API, specifying the Zone ID, and providing your email address and API key. The response will contain information about all of the DNS records associated with the domain, including their identifiers.

Here is an example command that you can use to get the DNS record identifiers:

curl --request GET \
  --url https://api.cloudflare.com/client/v4/zones/<zone_id>/dns_records \
  --header 'Content-Type: application/json' \
  --header 'X-Auth-Email: <email_address>' \
  --header 'X-Auth-Key: <api_key>'

Replace <zone_id>, <email_address>, and <api_key> with your actual values.

Update the DNS Record

Finally, you can use the DNS record identifier to update the DNS record. The following is an example bash script that you can use to update a DNS record:

#!/bin/bash

ip=`curl https://bytefreaks.net/what-is-my-ip | grep '<h1 style="text-align: center;"' | cut -d '>' -f 2 | cut -d '<' -f 1`;

ip=`echo $ip | cut -d, -f1`;

comment=`date +%Y-%m-%d\ %H:%M`;

curl --request PUT \
  --url https://api.cloudflare.com/client/v4/zones/<zone_id>/dns_records/<dns_record_id> \
  --header 'Content-Type: application/json' \
  --header 'X-Auth-Email: <email_address>' \
  --header 'X-Auth-Key: <api_key>' \
  --data '{
  "content": "'$ip'",
  "name": "www.bytefreaks.net",
  "proxied": true,
  "type": "A",
  "comment": "'"$comment"'",
  "tags": [],
  "ttl": 3600
}'

Replace <zone_id>, <dns_record_id>, <email_address>, and <api_key> with your actual values. You should also update the "name" field to match the name of the DNS record you want to update.

This script is used to update a DNS record using the Cloudflare API. It retrieves the current public IP address of the device running the script and then updates the specified DNS record on Cloudflare with the new IP address.

Here is a breakdown of each command in the script:

  • ip=curl https://bytefreaks.net/what-is-my-ip | grep ‘<h1 style=”text-align: center;”‘ | cut -d ‘>’ -f 2 | cut -d ‘<‘ -f 1“: This command uses the curl command to retrieve the public IP address of the device running the script from the website https://bytefreaks.net/what-is-my-ip. The output of this command is then piped through grep to find the line that contains the IP address. The cut command is then used to extract the IP address from the line.
  • ip=echo $ip | cut -d, -f1“: This command removes any commas from the IP address, which may be present if the IP address is in a format that includes additional information.
  • comment=date +%Y-%m-%d\ %H:%M“: This command generates a comment for the DNS record update. The comment includes the current date and time in the format YYYY-MM-DD HH:MM.
  • curl --request PUT \: This command sends an HTTP PUT request to update the specified DNS record.
  • --url https://api.cloudflare.com/client/v4/zones/<zone_id>/dns_records/<dns_record_id> \: This specifies the URL for the Cloudflare API endpoint for updating a DNS record. The <zone_id> and <dns_record_id> placeholders should be replaced with the actual zone ID and DNS record ID, respectively.
  • --header 'Content-Type: application/json' \: This specifies that the content type of the request is JSON.
  • --header 'X-Auth-Email: <email_address>' \: This specifies the Cloudflare account email address associated with the API key. The <email_address> placeholder should be replaced with the actual email address.
  • --header 'X-Auth-Key: <api_key>' \: This specifies the Cloudflare API key for the account. The <api_key> placeholder should be replaced with the actual API key.
  • --data '{ ... }': This specifies the JSON data to be sent in the request body. This includes the new IP address in the content field, the domain name in the name field, the record type in the type field, the comment in the comment field, and other optional parameters like the ttl. Note that the domain name at.put.cy is hardcoded in the script, and should be replaced with the actual domain name to be updated.

The code execution cannot proceed because MSVCP140_2.dll was not found. Reinstalling the program may fix this problem.

 in Applications / Windows  tagged Microsoft / MSVCP140_2.dll / obs / Open Broadcaster Software by

Introduction

Open Broadcaster Software (OBS) is a free and open-source streaming and recording software that is widely used by content creators. It allows users to record and stream high-quality videos and is compatible with various platforms. However, users may encounter issues while installing or using OBS on WIndows systems. One such issue is the missing MSVCP140_2.dll file error.

In this blog post, we will discuss this error in detail and provide a solution to fix it.

Error Description

When a user tries to install or launch OBS on their computer, they may encounter the following error message:

The code execution cannot proceed because MSVCP140_2.dll was not found. Reinstalling the program may fix this problem.

This error occurs because the system is missing the MSVCP140_2.dll file, which is a part of the Microsoft Visual C++ Redistributable package. OBS requires this package to function properly.

Solution

To fix the missing MSVCP140_2.dll error in OBS, follow the steps below:

Step 1: Download the Microsoft Visual C++ Redistributable Packages.

Visit the Microsoft website and download the following package:

Make sure to download the 64-bit version of each package that matches your system architecture.

Step 2: Install the Packages

After downloading the packages, install them on your computer by following the on-screen instructions.

Step 3: Restart OBS

After installing the packages, restart OBS and try launching it again. The missing MSVCP140_2.dll error should be resolved, and OBS should function properly.

Conclusion

In conclusion, the missing MSVCP140_2.dll error is a common issue while installing or using OBS. This error occurs because the system lacks the Microsoft Visual C++ Redistributable package. To fix this error, download and install the Microsoft Visual C++ Redistributable packages for Visual Studio 2015, 2017, 2019, and 2022 (64-bit version) from the Microsoft website. After installing these packages, restart OBS, and the error should be resolved.

Some important notes to keep in mind next time you create a password

 in Cyprus Cyber Security Challenge  tagged attack / hacker / password by

It is imperative that you understand why it’s important to avoid using patterns in your passwords, even if you try to make them more complex by including system information or a small random password.

Hackers can use various methods to guess passwords, including brute-force attacks, dictionary attacks, and social engineering techniques. One standard technique hackers use is to try to guess passwords based on patterns or common information, such as system names or random passwords.

Even if you combine a static base with system information and a small random password, this can still be guessed by a determined hacker. This is because hackers can use tools to scan your system for information and use that information to build targeted attacks against your account.

Additionally, hackers can also use social engineering techniques to try and guess your password. This could involve sending you a phishing email or creating a fake login page to trick you into entering your password.

To keep your accounts secure, it’s crucial to use strong, unique passwords that are not based on patterns or easily guessable information. A good password should be at least 12 characters long and include a mix of uppercase and lowercase letters, numbers, and special characters.

By creating a strong, unique password, you can help protect your online accounts from potential security breaches and keep your personal information safe. Remember to update your password regularly and never share it with anyone else.