You can open other ports using —> Network & Security —> Security Groups

Request to open

Goto top right side inside AWS account, and click on ? mark icon, it will open dropdown and click on support center.

It will take you to AWS Support Center page. click on Create case it will take you to the page with three radio button options, you need to select Server limit increase it will open search field, you will need to search with “ec2 email” and last click on EC2 email external link, as shown in below image.

You need to provide details like below.

Hello Amazonian

I will use Amazon SES to send email to reset passwords in case they request password reset. The email will always have an unsubscribe link that they can request to be removed from our list.

My web server is based in openSource technology which comes with below services to protect from spamming etc
Amavisd-new,
SpamAssassin,
ClamAV
Kindly approve my request for Amazon SES production access in the above mentioned region. Let me know if you have any questions.

Thanks

They are very fast to response, I often get in without 1 hour.

Hope you like this small post, if its helpful please share it on social media.

You may like other post too

The post Steps to open port 25 on EC2 instance – Amazon web service (AWS) appeared first on Otricks.com.

WebSocket is very useful pice of technology to communicate seamlessly from server to client, unlike HTTP it use full-duplex data transmission meaning, data can be transmitted in both directions on a signal carrier at the same time. To interact with webSocket we can use socket.io library which hides most of the stuff and provide clean API.

What is strapi?

It’s headless content management system, if this headless makes no sense then think like wordpress or Joomla content management systems (cms) they comes with themes which user can install and see something in action, however in headless CMS there are no theme system, user needs to create their own theme for website or they can consume data on mobile apps.

Strapi is open source nodejs based system, its based on Koa.js.com or follows same style of coding. Its comes with Rest API as well as graphql support too.

I don’t want to create chat-room example for this guide. May be We can create to booking system to send payload to Mars using space-x shuttle service, where user can book a cargo in the space-x rocket once space is allocated from space-x’s team, the user will get notification via WebSocket about cargo space.

It’s going to be very long post, hence I will create it in multiple steps. I will be pushing code to Github in every step so do checkout all the steps of the code.

I will try to implement following

• Create Angular application for frontend system (FE).
• Create user login (FE)
• Create protected route (FE)
• Create Strapi application for backend system (BE).
• Create sample API (BE).
• Create dummy user (BE).
• Start communication from Angular application to Strapi application.
• Identify user and based on user send socket messages.

Lets start building our frontend system first, I will call our fictional cargo booking company. space-XYZ .

Please click her to checkout frontend system.

The post How to use webSocket/Socket.io inside Strapi content management system. appeared first on Otricks.com.

These binlog files are very storage-intensive, most of the time for a small application each binlog file will be around 1.2GB.

Now imagine if you have 20GB disk-space it will eat up pretty much everything to the point where not a single kb is remaining for the server, if such thing happens, we even can’t run small commands like opening a file or editing a file etcetera.

As you can see in below image where It uses 100% of disk space 🙁

Some blog suggested that we can delete those files using myql> in terminal, however if you don’t have any space left we can’t even run sql in terminal.

The right way to remove binlog files.

If you are a root user to the system you can do following things to get it deleted in proper way.

login to the system via ssh and run below command, it will make you root user.

sudo -su

Run df -h to check current disk space information, it will show you something like below. check /dev/xvda1 section it consume all the space which I have it 🙁

Filesystem      Size  Used Avail Use% Mounted on
udev            236M     0  236M   0% /dev
tmpfs            49M  5.7M   44M  12% /run
/dev/xvda1       20G   20G     0 100% /
tmpfs           244M     0  244M   0% /dev/shm
tmpfs           5.0M     0  5.0M   0% /run/lock
tmpfs           244M     0  244M   0% /sys/fs/cgroup
/dev/loop0       92M   92M     0 100% /snap/core/8689
/dev/loop1       18M   18M     0 100% /snap/amazon-ssm-agent/1480
/dev/loop2       18M   18M     0 100% /snap/amazon-ssm-agent/1566
/dev/loop4       94M   94M     0 100% /snap/core/8935
tmpfs            49M     0   49M   0% /run/user/1000

To get more information about your database usage you can run du -hs /opt/bitnami/mysql/data for me, it’s 16 bg, which is way too much for small application.

16G	/opt/bitnami/mysql/data

To check all the big files (in space allocation) run below command, it will show list of culprits

du -hs /opt/bitnami/*/*/* |sort -rh | head -35

1.1G	/opt/bitnami/mysql/data/binlog.000017
1.1G	/opt/bitnami/mysql/data/binlog.000016
1.1G	/opt/bitnami/mysql/data/binlog.000015
1.1G	/opt/bitnami/mysql/data/binlog.000014
1.1G	/opt/bitnami/mysql/data/binlog.000013
1.1G	/opt/bitnami/mysql/data/binlog.000012
1.1G	/opt/bitnami/mysql/data/binlog.000011
1.1G	/opt/bitnami/mysql/data/binlog.000010
1.1G	/opt/bitnami/mysql/data/binlog.000009
1.1G	/opt/bitnami/mysql/data/binlog.000008
1.1G	/opt/bitnami/mysql/data/binlog.000007
1.1G	/opt/bitnami/mysql/data/binlog.000006
1.1G	/opt/bitnami/mysql/data/binlog.000003
1.0G	/opt/bitnami/mysql/data/binlog.000018
569M	/opt/bitnami/mysql/data/binlog.000004

At this point you even can’t open file via nano etc.txt or preform any other operation in the system as no space is left.

You can delete binlog.000001 to get some space, run rm binlog.000001 once it’s deleted you will be able to run nano command.

Now open binlog.index file using nano binlog.index and remove all the entries of binlog.0xxx from binlog.index file, once done save it and exit.

Run below to remove all fu(king binlog files at once, if you want you can remove mysqld.log files to as it might not be any use.

rm binlog.00*

After this if you run df -h you will get your space back. check /dev/xvda1 section 🙂

Filesystem      Size  Used Avail Use% Mounted on
udev            236M     0  236M   0% /dev
tmpfs            49M  5.7M   44M  12% /run
/dev/xvda1       20G  4.4G   15G  23% /
tmpfs           244M     0  244M   0% /dev/shm
tmpfs           5.0M     0  5.0M   0% /run/lock
tmpfs           244M     0  244M   0% /sys/fs/cgroup
/dev/loop0       92M   92M     0 100% /snap/core/8689
/dev/loop1       18M   18M     0 100% /snap/amazon-ssm-agent/1480
/dev/loop2       18M   18M     0 100% /snap/amazon-ssm-agent/1566
/dev/loop4       94M   94M     0 100% /snap/core/8935
tmpfs            49M     0   49M   0% /run/user/1000

Hope this will be helpful to someone.

I go beyond boundaries that trap me. Attachments and limitations in thinking are removed and I see people as actors playing roles sometimes negative and sometimes positive and scenes as passing phases, sometimes negative and sometimes positive. This experience translates into power in the consciousness as well as in words and actions.

You may check other informative article https://otricks.com/responsiveness-in-reactive-programming/

The post How to delete MySQL binlog files if you don’t have disk space left appeared first on Otricks.com.

Now I have switched from nodemon to new amazing ts-node-dev as stated in npm site

It restarts target node process when any of required files changes (as standard node-dev) but shares Typescript compilation process between restarts. This significantly increases speed of restarting comparing to node-dev -r ts-node/register ..., nodemon -x ts-node ... variations because there is no need to instantiate ts-node compilation each time.

I will show my vs code setup for typescript which auto recompile and uses ts-node-dev package for any file change event.

Setup vs code for typescript

Create a new project in your computer

mkdir dummyProject
cd dummyProject

I will be using npm as my package manager, let’s create a new package with default settings with below command

npm init -y

It will generate a new file as a package.json

{
  "name": "dummyProject",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC"
}

Add typescript, ts-node-dev and create new src folder with index.ts file inside.

npm install typescript ts-node-dev --save-dev

Open package.json file and add below script inside the scripts block.

"dev": "ts-node-dev --respawn --transpileOnly src/index.ts"
"dev:debug": "ts-node-dev --inspect=4321 --respawn --transpileOnly src/index.ts"

{
  "name": "dummyProject",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "dev": "ts-node-dev --respawn --transpileOnly src/index.ts",
    "dev:debug": "ts-node-dev --inspect=4321 --respawn --transpileOnly src/index.ts"
  },
  "keywords": [],
  "author": "",
  "license": "ISC"
}

Visual studio code debugging

Inside visual studio code, we can add a breakpoint in the typescript code which can stop at certain points. Inside your root directory of the current project.

mkdir .vscode
cd .vscode
touch launch.json

Paste the following into your launch.json which we have created the previous step.

{
  "version": "0.2.0",
  "configurations": [
    {
      "type": "node",
      "request": "attach",
      "name": "Attach to dev:debug",
      "protocol": "inspector",
      "port": 4321,
      "restart": true,
      "cwd": "${workspaceRoot}"
    }
  ]
}

Now do npm run dev:debug first in vs code terminal. once its’ started then click on the debug button from the left menu in VS code. it will open debugger panel something below.

Check out other tips such as How to secure ubuntu server

The post Ideal setup for working with nodejs typescript in VS code? appeared first on Otricks.com.

According to Ubuntu data, there are around at least 20 million users are using Ubuntu and that’s a very big number. It would be a gold mine for attackers who keep trying to get access to your server using a brute-force attack, for those who don’t know what the hack is brute-force attack?. its an attempt to crack username and password, using trial and error approach with the hope to get it correct for multiple time, if you keep your password or username very generic or easy to guess they might get into your system.

It’s a very old attack method, however, it’s still very effective and popular within the hacker community. You can read more about brute-force attack here.https://en.wikipedia.org/wiki/Brute-force_attack

It’s always a better idea to secure your system/service/server from such wicked people. Let’s get it done.

I will be using my Ubuntu 18.04.4 LTS (GNU/Linux 4.15.0-88-generic x86_64) machine.

Update your system first running below commands in the terminal, my assumption is you are already logged in with Root access using SSH.

apt-get update
apt-get upgrade

After a system update add Fail2ban, which is an invasion blocking software framework that protects servers from brute-force attacks, it’s written in the Python.

Fail2Ban scans log files like /var/log/auth.log and bans IP addresses conducting too many failed login attempts. It does this by updating system firewall rules to reject new connections from those IP addresses, for a configurable amount of time.

Fail2Ban comes out-of-the-box ready to read many standard log files, such as those for sshd and Apache, and is easily configured to read any log file of your choosing, for any error you wish.

Though Fail2Ban is able to reduce the rate of incorrect authentication attempts, it cannot eliminate the risk presented by weak authentication. Set up services to use only two factor, or public/private authentication mechanisms if you really want to protect services.

apt-get install fail2ban

Copy the configuration file and do changes

sudo cp /etc/fail2ban/jail.conf /etc/fail2ban/jail.local

sudo nano /etc/fail2ban/jail.local

Change the ban time from 600 (10 minutes) to 604800 (7 days) is guess this would be more than enough to have peaceful nights 🙂

Nest step is to install logwatch is the tool the aggregate all system logs and make meaningful decisions.

apt-get install logwatch

Logwatch can be configurated to trigger a daily email of your logs.

nano /etc/cron.daily/00logwatch

Add below line at the bottom of the cron job file and replace the example email with your own address.

/usr/sbin/logwatch --output mail --mailto mail@example.com --detail high

The post How to secure your Ubuntu server from brute-force attacks?. appeared first on Otricks.com.