tag:blogger.com,1999:blog-52611184902883916932026-04-29T08:55:07.768+01:00Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.comBlogger78125tag:blogger.com,1999:blog-5261118490288391693.post-25821807225894986932026-04-14T11:01:00.004+01:002026-04-14T11:04:05.170+01:00

A complete series covering TLS basics, DigiCert trust changes, certificate lifetime reductions, and automation for Linux users. Introduction Over the past few posts, I have covered the basics of TLS certificates, the DigiCert trust-chain changes affecting older hierarchies, the real certificate validity timeline, and practical automation steps for Linux admins. Full series TLS

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-77648420273811546472026-04-14T10:51:00.004+01:002026-04-14T11:04:30.408+01:00

Part 6 of 6 A practical 2026 checklist for TLS certificate trust changes, DigiCert chain updates, automation, and monitoring. Introduction If you do not want all the background detail and only want the practical action plan, this is the post to save. 2026 is important for two reasons: some older DigiCert trust paths are losing browser trust, and certificate lifetimes are on a path

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-32322945346178850392026-04-14T10:49:00.009+01:002026-04-14T11:04:39.708+01:00

Part 5 of 6 Shorter TLS certificate lifetimes mean manual renewal is no longer enough. Here is how Linux admins can automate renewals safely. Introduction Once certificate lifetimes start shrinking, the obvious question becomes: how do we keep up without turning certificate renewals into a monthly headache? The answer is automation. Use ACME-based renewal Most modern

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-6225063438723795372026-04-14T10:48:00.003+01:002026-04-14T11:04:49.870+01:00

Part 4 of 6 People keep saying certificate validity is dropping from one year to one month. Here is the real public TLS timeline and what it means. Introduction I keep hearing the same claim: certificate validity is going from one year to one month. That is not the full story. The real change is more gradual, but it is still a big operational shift. The actual timeline

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-78750481793590066012026-04-14T10:46:00.002+01:002026-04-14T11:05:02.160+01:00

Part 3 of 6 A practical Linux guide to inspecting TLS certificate chains with OpenSSL before DigiCert trust changes cause browser errors. Introduction Once you know that browser trust changes are coming, the next question is obvious: how do you check whether your own server is affected? The good news is that Linux gives you simple tools for this. One of the easiest ways is to

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-85697585364480841852026-04-14T10:42:00.004+01:002026-04-14T11:05:11.844+01:00

Part 2 of 6 Older DigiCert certificate chains are losing browser trust in 2026. Here is what is changing, who is affected, and why it matters. Introduction You may have heard people saying that Mozilla is no longer trusting old DigiCert certificates. That statement is directionally true, but it needs more detail. The issue is not that DigiCert as a whole is being distrusted. The

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-57654126840082958712026-04-14T10:40:00.002+01:002026-04-14T11:05:24.492+01:00

Part 1 of 6 A simple guide to TLS certificates, certificate chains, root CAs, and intermediates for Linux users, website owners, and beginners. Introduction If you run a blog, website, reverse proxy, API, mail server, or admin panel, you are already depending on TLS certificates. Many people use them every day without fully understanding how they work. That is normal. But with browser

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-67543627375600661612023-11-03T15:17:00.001+00:002023-11-03T15:17:29.523+00:00

You can migrate your Redis DB to OCI Cache on Redis using the following steps. You need to use a data dump tools such as pyredis-dump for getting serialised dump from your Redis DB. This tool can be used to take a serialised dump from any Redis node running in any cloud environments like AWS ElastiCache. So far, we are testing only single master Redis cluster.   [root@jay ~]# git

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-76841205491727036152023-10-27T17:15:00.002+01:002024-05-02T15:45:55.750+01:00

Redis is a private service and accessible only within the VCN or appropriately peered VCNs.   You can connect to the OCI Redis Clusters using the cluster endpoints provided.   To write to the redis cluster, connect using the Primary endpoint. To read from the redis cluster, connect using the Replica endpoint.   You may choose a client library your programming language

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-26769275721480411052023-10-27T16:22:00.002+01:002024-01-10T13:46:23.663+00:00

 OCI provisions private DNS endpoints for your Redis Cluster as follows.   - 1 Primary Endpoint always pointing to the Primary node. In case of a primary node failure, the primary endpoint will automatically failover to the new primary.   - 1 Replica Endpoint pointing to one of the Read replicas. If you have more than 1 read replica, the replica end point resolves to one of the

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-889592610989060322023-10-27T15:33:00.005+01:002023-10-27T16:08:33.902+01:00

OCI Redis Cache is GA as of now. You can launch Redis Cache clusters using Console, CLI, SDK, Terraform and so on.  Using Console : Launching a Redis cluster using OCI console is even easier.Just go to Databases --> Redis --> Clusters --> Create cluster and launch selecting required options.  Let’s see how to launch a Redis Cluster on OCI using CLI. Sample Command: # oci

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-74732440919374413112023-10-25T16:58:00.006+01:002023-10-25T16:58:38.932+01:00

If you have a FortiGate Firewall you might have encountered situation where Fortinet devices appear to have open TCP ports 2000 and 5060, even when firewalls are configured to block them. If an IPSec connection is configured, this even looks like a telnet connection can be established between the devices in each end of the tunnels on TCP 2000 and 5060. Security scans will flag it a threat. &

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-53215693515544687722023-10-23T16:45:00.002+01:002023-10-23T16:45:46.277+01:00

  If you are working on cloud environments like AWS, OCI you might have come across a requirement where you need to add custom settings on DNS like name servers, search domains and so on. Any changes to /etc/resolv.conf or the network configuration files will be reverted by the DNS server associated with the cloud virtual network.   There are many ways to set custom DNS

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-28467358632710533862023-10-18T13:02:00.000+01:002023-10-18T13:02:00.467+01:00

 Advanced Intrusion Detection Environment (AIDE) is an open-source utility designed to monitor and protect the integrity of files on a Linux system. AIDE creates a database of file attributes and uses it to perform regular checks for changes, additions, or deletions in system files, alerting you to potential security breaches. When properly used AIDE helps to protect the system internally,

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-88744103066104242252023-10-17T18:43:00.001+01:002023-10-18T09:00:16.202+01:00

  Linux servers are renowned for their resilience and security. However, even the most robust systems can fall prey to malware. When malicious software breaches your Linux server's defences, knowing how to eliminate it is paramount. In this comprehensive guide, we will walk you through the steps necessary to remove malware from your Linux server, including utilizing the helpful

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-47379075392843184872023-09-28T11:51:00.004+01:002023-09-28T11:51:27.145+01:00

 As cybersecurity threats evolve, older SSL/TLS protocols and ciphers that were once considered secure have become deprecated due to vulnerabilities and weaknesses. Here are some of the deprecated SSL/TLS protocols and ciphers: Deprecated SSL/TLS Protocols: 1.     SSLv2: SSL version 2 is highly insecure and has numerous vulnerabilities, including susceptibility to

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-12205456707747266212023-09-28T11:48:00.002+01:002023-09-28T11:48:27.231+01:00

The foundation of secure communication on the internet relies heavily on TLS/SSL cipher suites. These suites dictate the algorithms used to encrypt and decrypt data, ensuring that sensitive information remains private and protected. In this article, we'll delve into the world of TLS/SSL cipher suites, examining how they work, their components, and their importance in

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-7658599668053173702023-09-28T11:37:00.001+01:002023-09-28T11:37:07.272+01:00

The use of SSL/TLS (Secure Sockets Layer/Transport Layer Security) encryption is fundamental to the security of internet communication. When you connect to an HTTPS website, your browser engages in a complex process of validating SSL/TLS certificates to ensure secure and trustworthy data transfer. In this article, we'll unravel the mystery behind SSL/TLS certificate chain validation and how it

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-50632655438752711872023-09-27T11:33:00.003+01:002023-09-27T11:33:43.200+01:00

The efficient management of physical RAM (Random Access Memory) is crucial for the smooth operation of any operating system. Linux, renowned for its performance and reliability, employs a robust memory management system to optimize the utilization of physical memory resources. In this article, we'll delve into how Linux manages physical RAM, exploring the mechanisms and algorithms that make it

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-30626850600317118162023-09-27T11:28:00.001+01:002023-09-27T11:28:09.287+01:00

Memory leaks can be a silent killer in software development. They gradually consume system resources, leading to performance degradation and even application crashes. Detecting and addressing memory leaks is a critical aspect of maintaining robust and efficient software. In this article, we'll explore memory leak detection techniques and strategies to help you keep your codebase leak-free.

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-8476518660099323032023-09-25T12:46:00.004+01:002023-09-25T12:46:37.039+01:00

 The free command is a valuable utility in the Linux arsenal, providing insights into your system's memory usage. It presents a snapshot of the memory utilization and helps you gauge the health of your system's RAM. In this article, we'll explore how to read and interpret the output of the free command to make informed decisions regarding your system's memory management. The Basics of the

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-84212435255935756512023-09-20T00:17:00.002+01:002023-09-20T09:24:37.374+01:00

ss Command Cheat Sheet This cheat sheet provides an overview of the ss command and its commonly used options for examining socket statistics and network connections in Linux. Adjust the options as needed to match your specific requirements when working with ss.  1. Displaying Sockets: ss: Display a summary of all sockets.ss -t: Display TCP sockets.ss -u: Display UDP

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-51357922307355899812023-09-19T23:30:00.001+01:002023-09-20T00:20:36.322+01:00

Several of the most used Linux commands/tools such as ifconfig, netstat, route is deprecated. It’s time to start using the versatile ip command line utility.   Ip command line utility provided by the ‘net-tools’ package is used for various network administration tasks on Linux nodes.   Syntax of the ip command line utility:   # ip [ OPTIONS ] OBJECT {

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-44976916330343959172023-09-07T17:00:00.001+01:002023-09-07T17:01:44.302+01:00

  We all heard that our bellowed DNS lookup tool ‘nslookup’ is getting deprecated. Even though the nslookup tool has been resurrected and is not going anywhere, its better to learn about another cool name lookup tool – ‘dig’.  What is ‘dig’? 'Dig,' short for Domain Information Groper, is a command-line utility designed for DNS queries. Dig is super useful for

Jayhttp://www.blogger.com/profile/08928753128432395715noreply@blogger.com0tag:blogger.com,1999:blog-5261118490288391693.post-13093900204126183112023-09-01T17:46:00.001+01:002023-09-01T17:47:05.998+01:00

  In today's digital age, where fast and reliable network connectivity is a necessity, ensuring that your network performs at its best is crucial. This is where iperf3, a versatile and powerful tool, comes into play. In this blog post, we'll dive into how you can use iperf3 to conduct network performance tests and optimize your network for peak efficiency.  What is

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