Fix routines:X509_check_private_key:key values mismatch in 2 Ways

For SSL key values mismatch issue, it means the private key file does not match the certificate. There are two main reasons. key values mismatch in private key, CSR, and certificate file. certificate chain order is not correct Error message:Cannot load SSL private key file. Error: error: 0B080074:x509 certificate routines:X509_check_private_key:key values mismatch. What is SSL […]

Check Wildcard Certificate in SSL with Examples

A wildcard certificate is a specific form of the certificate used in TLS/SSL instances. It is a single certificate with a wildcard character (*) in the domain name field. This allows the certificate to secure multiple subdomain names (hosts) pertaining to the same base domain. For example, a wildcard certificate for *.(domainname).com, could be used […]

Understanding SSL Certificate PEM File and SSH PEM File with Examples

PEM (originally “Privacy Enhanced Mail”) file was initially invented to make e-mail secure. Now it is an Internet security standard. PEM file is the most common format for X.509 certificates, CSRs, and cryptographic keys. What is a PEM file A PEM file is a text file containing one or more items in Base64 ASCII encoding, […]

Convert SSL certificate from CRT to PEM

There are two major encoding schemes for X.509 certificates and keys: PEM (Base64 ASCII), and DER (binary). DER (Distinguished Encoding Rules) is a data object encoding schema that can be used to encode certificate objects into binary files. PEM (Privacy Enhanced Mail) is an encrypted email encoding schema that can be borrowed to encode certificate […]

4 Ways to Check Disk Partition with Examples in Linux

The first thing that we need to know is there is no C drive or E drive in Linux. We will see something like /dev/sda, /dev/sdb, /dev/sdc, … etc. instead. The dev is short for device. The sd was short for Small Computer System Interface (SCSI) mass-storage driver. /dev/sda – The first SCSI disk SCSI […]

Check Linux Block Device with Examples

A block device is a storage device that moves data in sequences of bytes or bits (blocks). These devices support random access and generally use buffered I/O. Examples include hard disks, CD-ROM drives, and flash drives. A block device can be physically attached to a computer or accessed remotely as if it were physically attached […]

Create AWS S3 Bucket with AWS Cli

Amazon Simple Storage Service (Amazon S3) is a scalable, high-speed, web-based cloud storage service. The service is designed for online backup and archiving of data and applications on Amazon Web Services (AWS). Amazon S3 was designed with a minimal feature set and created to make web-scale computing easier for developers. What is AWS S3 bucket? […]

Understanding AWS S3 with Examples

Amazon S3 (Simple Storage Service) is a scalable, high-speed, low-cost web-based service designed for online backup and archiving of data and application programs. It allows to upload, store, and download any type of files up to 5 TB in size. Amazon S3 can be integrated with any application or services offered by Amazon, such as […]

Understanding AWS VPC with Examples

Amazon Virtual Private Cloud (VPC) is a service that lets us launch AWS resources in a logically isolated virtual network that we define. Amazon Virtual Private Cloud (Amazon VPC) enables us to launch Amazon Web Services resources into a virtual network we’ve defined. This virtual network resembles a traditional network that we’d operate in our […]

Understanding FQDN with Examples

A Fully Qualified Domain Name (FQDN) is the complete domain name of a specific computer, or host, online. A FQDN gives its precise location in the hierarchy of DNS records. It is the complete address for websites and other computers and entities accessing the Internet resolving to the root domain. An FQDN is comprised of […]