nanusdad

How to resolve - unable to verify the first certificate in NodeJS

Connect using SSL to ascertain the error

openssl s_client -connect foo.badssl.com:443 -servername foo.badssl.com

Save output to tmp file

openssl s_client -connect foo.badssl.com:443 -servername foo.badssl.com | tee /tmp/logcertfile

Find issuer and CRT file

openssl x509 -in /tmp/logcertfile -noout -text | grep -i "issuer"

Get the intermediate certificate from issues

curl --output sectigo.crt http://crt.sectigo.com/SectigoRSAOrganizationValidationSecureServerCA.crt

Convert to pem file

nanusdad

Creating systemd service

Create Systemd Service File

sudo touch /etc/systemd/system/foo-daemon.service
sudo chmod 664 /etc/systemd/system/foo-daemon.service

Edit service file

vi /etc/systemd/system/foo-daemon.service

nanusdad

1. Run Software Update

Make sure everything is up to date in the App Store

2. Install Homebrew

1. Open a terminal window and execute the Homebrew install script:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

nanusdad

Simple ExpressJS API to use local sendmail

API code

const express = require('express');
const nodemailer = require('nodemailer');
const app = express();

app.use(express.json());

// Configure Nodemailer to use the local sendmail service

nanusdad

Setting up SSL cert with nginx

1. Copy the .crt file and encrypted .key file to nginx server
2. Decrypt the .key file

openssl rsa -in encrypted.key -out decrypted.key

4. Concatenate the .crt and and encrypted .key file

cat domain.crt encrypted.key > domain.pem

nanusdad

Setting up sendmail relay on Ubuntu 22.04 (with PHP)

Test relay, needs host and port

One can use telnet to test; output will be similar to below. (use your email instead of joe@doe.com)

telnet 172.16.10.100 8081
Trying 172.16.10.100...
Connected to 172.16.10.100.
Escape character is '^]'.
220 mailagent.test.com ESMTP Postfix (Ubuntu)

nanusdad

PopOS (Ubuntu based) Install Related Quirks

APT proxy

sudo vi /etc/apt/apt.conf.d/proxy.conf

#Add the following lines:

Acquire::http::Proxy "http://username:password@proxy-server-ip:8181/";
Acquire::https::Proxy "https://username:password@proxy-server-ip:8182/";

nanusdad

Docker configuration behind HTTP or HTTPS proxy

Create http-proxy configuration file

sudo mkdir -p /etc/systemd/system/docker.service.d
sudo vi /etc/systemd/system/docker.service.d/http-proxy.conf

Add lines similar to the ones below and save file

[Service]
Environment="HTTP_PROXY=http://proxy.example.com:3128"

nanusdad

Raspberry Pi - Getting hardware information

cat /proc/cpuinfo                             # CPU info
cat /sys/firmware/devicetree/model            # Model info
cat /proc/version                             # Software info
free -h                                       # RAM Details

nanusdad

Alfresco on Docker cheatsheet

Create PostgreSQL dump

# find postgresql container ID
sudo  docker ps | grep postgres | awk '{ print $1 }'

# open shell on container (replace container id)
sudo docker exec -it cb96ca00911e /bin/bash