Configuring an SMTP Server on Oracle Cloud Infrastructure can be a useful way to send email messages from your applications or services. However, Oracle Cloud Infrastructure will block Port 25 by default and it cannot be removed by configuring engress rule in the security list. To bypass it, you will need to create an Email Relay in the Oracle Cloud Infarstracture. In this blog, I will show you how to configure the SMTP relay on Oracle Cloud Infrastructure (OCI). ...

1. Compress a folder To compress a folder in Linux, you can use the tar command. The tar command is used to create, manage, and extract files that are archived in the tar format. To compress a folder, you can use the -czvf flags, which tell tar to create a compressed archive, use gzip compression, be verbose, and use the file name that follows. First, navigate to the directory containing the folder you want to compress. Then, run the following command: ...

To use scp to download a file from a remote server to your local machine, you can use the following syntax: scp username@host:/path/to/remote/file /path/to/local/destination This will download the file located at /path/to/remote/file on the remote server, and save it to /path/to/local/destination on your local machine. You will need to replace username with your username on the remote server, host with the hostname or IP address of the remote server, and /path/to/remote/file and /path/to/local/destination with the actual paths to the remote file and the local destination, respectively. ...

DKIM (DomainKeys Identified Mail) is an email authentication method that allows the sender of an email to associate their domain name with the email message. This allows the recipient’s email server to check that the email message is authorized by the sender’s domain and has not been tampered with during transit. DKIM uses cryptographic signatures and public-key cryptography to verify the authenticity and integrity of email messages. When an email is sent, the sender’s mail server generates a digital signature for the message, which is then added to the email’s headers. The recipient’s mail server retrieves the sender’s public key from a DNS record and uses it to verify the signature. If the signature is valid, the recipient’s mail server can be confident that the email is from the domain it claims to be from and has not been altered in transit. ...

SMTP stands for Simple Mail Transfer Protocol. It is a protocol used for sending email messages between servers. Most email systems that send mail over the Internet use SMTP to send messages from one server to another, and to deliver messages to local mail clients like Microsoft Outlook or Apple Mail. An SMTP server is a computer that is responsible for sending and receiving email messages. It uses the SMTP protocol to communicate with other email servers, to receive messages from local clients, and to deliver messages to local clients. ...

Few months ago, I wrote a post about DroneCI: How to configure pipeline to build and push docker image. It worked well for multiple personal projects of mine. However, recently I am working on a new project which I want to deploy the image in the VPS instances with different platforms and architecture. 1. Solution Thanks to the Drcone CI plugin drone-docker-buildx, the task becomes a lot of easier. Here you go. ...

When I first time built a Golang project from VS Code wsl mode, I got the below error: Build Error: go build -o /home/oscar/source/github.com/xx/xx/__debug_bin -gcflags all=-N -l . # runtime/cgo cgo: C compiler "gcc" not found: exec: "gcc": executable file not found in $PATH (exit status 2) My first reaction for this error is to install the gcc compiler in my Windows environment. However, the solution is actually to install gcc compiler in the wsl environment. ...

If you just started to use WSL, you may encounter the issue that You only can access your service hosted in the WSL from the host by localhost, but not the IP address. For example, you have a web service that listens to port 8080. In your web browser, you can browse the site with http://localhost:8080, but http://127.0.0.1:8080. The reason is that you need to use the WSL IP address. An easy way to find the address is to execute the below command in WSL terminal. ...

1. Error 1: fatal: could not read Username for 'https://github.com': terminal prompts disabled The issue appears when I tried to download a private golang repository by the command go get github.com/oscarzhou/private-helloworld. The completed error shows as below: % go get github.com/oscarzhou/private-helloworld go: module github.com/oscarzhou/private-helloworld: git ls-remote -q origin in /Users/oscarzhou/go/pkg/mod/cache/vcs/c5fb5660c8bfa54f1b957fc4e651ac76f19b939fc9015bf3bcbc21a34c925af7: exit status 128: fatal: could not read Username for 'https://github.com': terminal prompts disabled Confirm the import path was entered correctly. If this is a private repository, see https://golang.org/doc/faq#git_https for additional information. If you have already googled this issue, you may find that most of the answers tell you to configure your git as shown below: ...

1. Error This issue happens when I run the command wget https://github.com/docker/compose/releases/download/v2.10.2/docker-compose-linux-x86_64 in my Ubuntu WSL. The completed error looks like below: The extracted error is >> connected. >> ERROR: cannot verify objects.githubusercontent.com's certificate, issued by ‘CN=ospanel’: >> Unable to locally verify the issuer's authority. >> ERROR: certificate common name ‘localhost’ doesn't match requested host name ‘objects.githubusercontent.com’. >> To connect to objects.githubusercontent.com insecurely, use `--no-check-certificate'. You can see there are basically four highlight errors above and many answers for each error if you google them. I had tried the below workarounds in WSL: ...