ENTERPRISE AT A FAIR PRICE MOVING FROM RHEL TO CENTOS

You can have the best available enterprise Linux at an affordable price by migrating from Enterprise Linux to CentOS. based on the same OS appearing on a server via the Linux in the enterprise character-based Bash shell, but they are the same.

Linux is today’s server operating system of choice. It’s not just the kernel. Numerous major IT open Businesses of all sizes and in all industries have turned source programs run on Linux, including: to this safe, reliable, and powerful operating system.

Linux wasn’t originally built with the enterprise in mind but, rather, for personal computers. As , WEB SERVERS then a graduate student, wrote in 19911: “I’m doing a Apache and Nginx (free) operating system (just a hobby, won’t be big and professional like gnu) for 386(486) AT clones.” MAIL SERVERS But that changed dramatically in 2003. Red Hat, initially Sendmail and Dovecot founded in 1995 as a software catalog business, decided to focus on delivering an affordable, customiz- able Linux system for businesses’ server needs, according to founders and .2 DATABASE MANAGEMENT SYSTEMS At the time, many people were unhappy3 with Red Hat’s MySQL, Postgres, and MariaDB focus on the enterprise. It wasn’t just customers. , then Red Hat’s vice president of engineering and now the company’s president of products and The primary reason Linux and open source software 4 technologies, told Ars Technica in 2012: “We had some have become the heart of modern IT is the GNU level of turmoil inside the company with going to this General Public License version 2 (GPLv2). Under this new model.” He was referring to many of the company’s license, a user can copy, repackage, sell, give away, or engineers, some of whom left over the decision. change the code in any way. The caveat is that if the code is distributed, the same rights must be passed on. Yet today, with Red Hat’s having reported that it is well on its way to being the first $1 billion-per-quarter open This means that anyone who works on Linux and then source company, the change in direction has turned distributes the code must share their work. This out well. And it has spun out many business Linux approach has made Linux the most successful of all distributions, including CentOS, Debian, Ubuntu, and open source projects. And it’s why there are several SUSE Linux Enterprise Server (SLES). Of all these, Red Linux server distributions. Hat Enterprise Linux (RHEL) has emerged as the most popular and important enterprise Linux. RHEL became a leader in this market because it focused on the enterprise earlier than its competitors. The GPL and open source It devoted focused programming work from day 1 toward securing Linux and making it better for business software users. Today, Red Hat is the de facto enterprise server standard. The various Linux distributions are all built on the same foundation: the . It may take an expert eye Yet that position is being challenged by CentOS. to spot that Android running on your smartphone is

1 https://en.wikipedia.org/wiki/History_of_Linux 2 http://www.zdnet.com/article/from-linux-to-cloud-why-red-hat-matters-for-every-enterprise/ 3 http://practical-tech.com/operating-system/why-linux-users-hate-red-hat/1728/ 4 https://arstechnica.com/information-technology/2012/02/how-red-hat-killed-its-core-productand-became-a-billion-dollar-business/

2 More pragmatically, Red Hat and CentOS joined forces CentOS: The free RHEL in early 2014. Red Hat made this move because, as Red Hat states on its FAQ site: “Success begins with commu- alternative nity-powered innovation… and, in turn, [creates] more demand for RHEL.” CentOS, an acronym for Community Enterprise Operating System, takes RHEL’s source code and Although CentOS is RHEL’s technical equivalent, it’s not compiles it into its own free Linux distribution. CentOS the same commercially. The CentOS community isn’t on can’t legally use Red Hat’s trademarks, so its developers the hook to provide support and training or offer take out the logos, links, and Red Hat–specific code guaranteed service-level agreements (SLAs). Its goal has repositories. They then recompile the code and make it been to give business users access to RHEL’s robust available as CentOS. code—without the need to pay for support.

CentOS is binary-compatible with Red Hat. By building CentOS earns customer loyalty by giving businesses the on top of RHEL, CentOS retains RHEL’s technical best of both worlds. On one hand, you get Red Hat’s advantages. CentOS also stays in step with RHEL. For enterprise-quality operating system. On the other, example, Red Hat released RHEL 7.4 on August 1, 2017, CentOS is completely free and open source. and then CentOS released CentOS Linux 7.4, on September 13, 2017. On the application side, how close is CentOS to RHEL? Red Hat recently moved its repositories over to Why does Red Hat allow this? As , Red CentOS’s own mirror. Their core software programs are 5 Hat’s CEO and president, recently wrote in a company identical. Also, CentOS is compatible with major blog post: “Open source is the driving force behind enterprise apps. For example, it can run Oracle much of the technology innovation.” Database, SAP, and Salesforce.

CentOS adoption among enterprises has risen rapidly

By 2010, CentOS By 2017, 85% of Today, CentOS is CentOS runs at There are more was the leading websites used by more least 300,000 of than 13,000 web server (on-premises and than 100,000 the Internet’s CentOS instances operating system, in the cloud) companies.8 web services.9 running on with almost 30% were running Amazon Web of all Linux noncommercial, Services (AWS).10 servers.6 unpaid-for Linux distros such as CentOS.7

5 https://www.redhat.com/en/blog/future-open-seizing-opportunity-open-source 6 https://w3techs.com/blog/entry/highlights_of_web_technology_surveys_july_2010 7 Gartner, “How to Decide Whether Free Linux is a Viable Option to Paid Linux,” April 14, 2017 8 iDataLabs: https://idatalabs.com/tech/products/centos 9 Netcraft November 2017 Web Server Survey 10 The Cloud Market, EC2 Statistics, as of February 2018

3 That level of cost savings isn’t typical. Most companies The business case for don’t have rollouts quite that large, but it is common to see savings of roughly 50%, primarily from eliminating migration to CentOS license fees.

CentOS is essentially a “move and drop” replacement Many enterprises start by investigating how CentOS for RHEL, making migration relatively easy while staying works for them on the edge with nonproduction or within the Red Hat operating system family. non-mission-critical servers and data centers. This helps prove that CentOS and RHEL are functionally The primary reason companies are moving from RHEL identical. to CentOS is price. And that’s about licensing and support costs. And it leads to another area of cost savings: training. If your administrators are already comfortable with Linux, Let’s break it down. With Red Hat, you must pay specifically RHEL, your staff won’t need CentOS training. multiple licensing fees for each product such as the RHEL server, virtual machine, high-availability add-on, load balancer add-on, and so on. For a typical midsize More reasons to switch business with 1,000 servers and standard support, these would be the licensing fees: Another reason companies make the switch is to be free from a closed ecosystem. Now, when you think “closed” software ecosystem, you’re probably thinking Cost Comparison Apple or Microsoft. Red Hat has its own way of keeping you penned in. RHEL CentOS approximately vs For instance, a large retail enterprise with a geographically distributed brick-and-mortar network $800,000 $0 wanted to do more than cut costs. It also wanted to free itself from the RHEL ecosystem so it could more Sometimes those savings are greater. Take, for easily scale. The company needed the flexibility of instance, a large enterprise mobile communications being able to choose both the software it needed and company that recently moved to CentOS: how it was deployed to match its use cases. For example, when it came to tools for management and DevOps, the retailer wanted to make its own choices. By migrating to CentOS, it achieved that level of scalability and flexibility. Taking into account Others businesses migrate away from Red Hat because everything from RHEL they aren’t happy with the level of support. They want licenses to subscription quicker access to experts, including system architects. support and maintenance, it These are all reasons why companies wanting to saved about $20 million. migrate to CentOS are turning to OpenLogic That’s substantial enough to CentOS support from Rogue Wave Software. get the attention of even global companies’ CFOs.

4 Supporting CentOS: Why OpenLogic

At one time, Linux technical knowledge and skills were uncommon. That’s no longer the case. Thus, with the right staffing, your IT department can handle day-to-day problems.

However, there are typically IT challenges that are outside of your staff’s expertise. After all, 80% of technical support problems deal with issues beyond a single software package.

OpenLogic offers the same level of support with CentOS that Red Hat offers with RHEL. But OpenLogic goes beyond the CentOS operating system and provides support for mission-critical apps.

Its staff members are experts in Linux as well as all the software that makes up the stack, such as Apache, MySQL, PHP/Python/Perl, Tomcat, JBoss, WildFly, PostgreSQL, and ActiveMQ. OpenLogic continues to add new technologies as enterprises add more open source programs to their data centers. For instance, it has supported Docker for years.

OpenLogic does this by providing direct access to Tier 3 and 4 enterprise architects. No escalation path is required. For example, when your IT team currently runs into a technical issue, the support call often runs through the typical call center gauntlet, with junior people trying to triage the issue. With OpenLogic, that call goes straight to an expert—typically with 10 to 15 years of enterprise architect experience—who can immediately start solving the problem.

The company provides guidance, training, and solutions for troubleshooting issues and optimizing CentOS deployments, with competitive pricing.

Compare RHEL with OpenLogic CentOS fees. To run the numbers and see the savings on each platform, click here to go to the CentOS cost savings calculator.

5 Even if your software vendor says it supports only Addressing the need for security RHEL, its applications will likely work on CentOS. Vendors typically say their products run only with RHEL Security is on everyone’s mind, but especially for because they haven’t tested CentOS. business and IT. Besides providing a standard CentOS distribution, OpenLogic also offers security-hardened Of course, each vendor has its own support policy. You CentOS images. These have been certified to standards can check to see if OpenLogic will support your app. set by the Center for Internet Security and OpenSCAP The company can, in turn, work together with you and and use Security-Enhanced Linux (SELinux). your vendor to remediate problems. Security-hardened CentOS reduces the operating For popular, widely deployed enterprise open source system’s attack surfaces. For example, it sets minimum packages, OpenLogic offers the same SLAs and guaran- password length; locks inactive user accounts; removes tees across the entire stack. Its SLAs include 24 x 7, unused software (FTP servers); verifies file permissions; one-hour response time and guaranteed workarounds. and provides reporting and auditing functions for changes to the network, access rights (sudoers file), and As for CentOS, OpenLogic quickly provides patches and kernel loading/unloading. hot fixes via a dedicated, secure repository. It does this without waiting for the CentOS community to catch up. OpenLogic supports CentOS on far more than just This feature enables you to maintain a current and in-house servers and data centers. For example, it tested version of CentOS, including the fixes you need creates and manages the official CentOS images for for keeping systems running. Amazon Web Services (AWS) and Microsoft Azure. In Azure’s case, OpenLogic creates and maintains Micro- For instance, OpenLogic immediately followed on Red soft’s official CentOS image. OpenLogic also supports Hat’s heels in releasing CentOS patches for the CentOS on Google Cloud. Meltdown and Spectre vulnerabilities. The reverse is also true: RHEL 7.4 includes some fixes made by OpenLogic CentOS developers.

6 The majority of the migration includes low-time/low-risk OpenLogic RHEL-to-CentOS applications. These are boilerplate applications such as web servers or programs not running in production—that is, migration process apps that don’t necessarily need as much attention.

Before anything gets under way, the OpenLogic team Sometimes as many as 80% of apps fall into this category, kicks off the process with a thorough assessment of which can generate both license and cost savings from goals and objectives. the migration’s first steps. Demonstrating low-risk cost savings at the start makes it easier to get executive buy-in During this stage, expectation levels are set. For for the rest of the migration. example, the assessment may determine that you don’t need the latest and greatest software. That said, 70% of In addition, your teams get the opportunity to see what the the time, OpenLogic provides architectural guidance, process looks like. As the deployment continues, your IT with your own IT staff handling the deployment. This organization’s trust and confidence build and the migration saves you even more money. But if your IT department can transition to applications of greater complexity. is lean or not at the right skill level, OpenLogic can handle the conversion. Other applications, such as C++ apps that are more tightly coupled to the operating system, may take longer to Next is a comprehensive software audit. In this phase, migrate. Sometimes they must be built in a staging OpenLogic looks not only at the open source packages environment to ensure that they’ll build properly and that that underpin your applications but also at different all the dependencies are in place. business unit and end user programs in use. This process is useful for both sides. For a successful Applications that typically take longer to migrate include: conversion, OpenLogic needs to understand which programs you’re using and how they’re being used. It Those that have many unit test cases also may uncover out-of-date programs as well as Those with numerous endpoints—such as databas- software that hasn’t been used in years for which you’re es, message brokers, or content repositories—that still paying license fees. need to be integrated and have their networking set up properly The migration road map It takes diligence at the beginning to build this inventory Then OpenLogic helps create a migration road map that and set of qualifiers, yet doing it right eliminates the kind prioritizes applications by their degree of difficulty and of chaos that can happen with migrations that are less complexity, taking into consideration conversion planned and organized. difficulties, potential downtime, and versioning issues. The goal is to make sure all programs are running in the OpenLogic uses Gartner-style quadrants to create this same way so that there’s no disruption. Ideally, your road map. business units will never know that their production applications are now running on CentOS.

Inventory and prioritize: Reduce your risk

A. Identify what to migrate: Business B. Assess time to migrate: Technical Inventory your apps. Categorize migration risk for Starting with lower risk apps, categorize technical each by need for support/responsiveness. risk and time to migrate.

Large OSS deployment Highly integrated • • Critical apps • Reporting & metrics OS-specific apps/code • • Key infrastructure • Key internal expertise Lower-level languages • • Potential for large revenue loss •

• Publicly-hosted SAAS • Isolated Prototyping & testing • Cross-platform • Not significant • Isolated systems languages/frame works Unchanging configs • High-level languages NEED FOR FAST • TECHNICAL RISK SUPPORT RESPONSE

NEED FOR SUPPORT APP EVOLUTION OVER TIME TIME TO MIGRATE RISK: LOW MED HIGH

7 Migration types and stages

There are essentially two types of migration:

Offline, where you’re not operating on the live production system Live, where the migration is carried out on a live production system

The offline migration process

A nonlive, offline migration involves installing the operating system and the applications that need to be configured and then staging the role of that migrated system to do testing.

The goal is to ensure that the migrated CentOS system works as well or better than the legacy RHEL environ- ment. Once that’s established, you decide whether to move forward with the migration plan or roll it back. With a nonlive offline migration, you can get to the final step and still decide it’s a no-go.

This type of migration comes with extra costs. There are staffing costs to perform the installation and configura- tion. Further, it may involve pulling in your development team, which could stall other business units’ program- ming projects.

Naturally, there are physical and virtual hardware costs. Nonlive, offline migrations are typically done in parallel with an existing system. That means standing up new systems in the data center that are functionally reacha- ble in the same way as your production system. This way, if you decide to move forward with the migration, you can quickly cut over from your old production system to the newly migrated one.

The live migration process

Live migrations work best if you’re already using RHEL with open source stacks, such as LAMP, portable Java environments, or containerized applications.

The time savings—compared to installing and configur- ing the operating system and applications to operate exactly like the existing system—can be significant. OpenLogic recommends a fresh backup of the entire system. That way, even in a worst-case scenario, you can easily roll back.

After the fresh backup has been made (and checked!), the next step is to remove the Red Hat–specific OS packages. Generally speaking, these tie the operating system to (RHN).

8 Then it’s time to download and install a minimal set of CentOS packages. This step is done manually, because the system is still pointed toward Red Hat for package updates. So the CentOS packages are downloaded and installed, and they then replace a small handful of Red Hat–type packages, which points your system to the CentOS repository.

The next step is cleaning and rebuilding the package cache. It’s important to make sure there’s no old, stale data, so that when it’s rebuilt, the package cache will use only the CentOS repository.

After that, the system performs an upgrade. This is what converts the system from RHEL to CentOS.

And finally, just like in the offline migration path, the system is tested. Make sure the migrated system is working as well as or better than the original system.

Then make the final decision: either approve the migrated system or roll back via the backups.

Moving from RHEL to CentOS is easy, but it’s difficult to migrate from CentOS back to RHEL. That’s why full system backup is so important. If it is necessary to roll back, it is best to rely on your disaster recovery plan to rebuild the original system. Even if you plan to utilize a live migration, you should test with a nonproduction copy of the system first.

The timeline

How long will all of this take? It depends. Although every company is different, it typically takes three months to migrate low-risk applications, and for high-risk apps, it can take up to a year.

However, you’re unlikely to experience downtime. RHEL to CentOS is pretty much an apple-to-apple conversion.

The bottom line

The primary reason to move from RHEL to CentOS with OpenLogic: lower total cost of ownership. But there’s also the ability to maintain best-of-breed Linux technol- ogy and retain top Linux security—all while increasing software flexibility.

9 Other programs were assessed as mission-critical with Talking points: A case higher migration risks, so they would be staged over time. These apps included a back-of-house JBoss study of a successful application for internal use and several legacy C++ CentOS migration programs for stock market estimates. Another consideration was which OS version to use. A midsize financial analysis company found that its IT The company was running RHEL 6.7. With RHEL expenses were increasing year over year, primarily due Extended Update Support (EUS), this version would see to an annual increase in RHEL licensing fees. With 1,000 support until November 30, 2020. There was discussion RHEL servers, that yearly fee increase added up fast. about moving to CentOS 7.4, its version of RHEL 7.4, but OpenLogic suggested moving to CentOS 6.7 for an The company’s requirements for a move to apples-to-apples switch, rather than a migration and a CentOS included: modernization all in one move. Once CentOS was in place and running smoothly, updating the operating system could be considered. CutCut costs costs Following the advice of OpenLogic, the financial analysis ImproveImprove its its IT IT support support model model company first ported its front-facing website from RHEL to CentOS. RetainRetain its its existing existing infrastructure infrastructure “The website is a core, highly visible program for us,” says the company’s CTO. “Because that migration went Make the most of its existing software stack Make the most of its existing software stack so smoothly, it made both our IT staff and, more importantly, our executive team comfortable,” making it MinimizeMinimize training training costs costs easier to move forward with the CentOS migration.

AvoidAvoid application application downtime downtime With regard to ongoing support, the company’s in-house staff was determined to be able to handle day-to-day problems, and it decided to use OpenLogic The firm turned to OpenLogic for assistance with the support only for larger issues. migration. “The cost savings were in line with our expectations,” The first step was to create a solid inventory of the says the CTO. “Frankly, the overall process was easier company’s applications. That helped the firm decide on than we thought it would be, and the support we get a timeline. For example, foundational from OpenLogic is better than what we previously had. programs—Apache for web servers, MariaDB for They readily share their expertise with our IT team, databases, and WordPress for the front-end web giving us the feeling of being within a community of content management system—were ready to migrate developers.” immediately with existing setup and configuration files.

Find out more. Click here to request a free consultation to discover how easy it is to migrate to CentOS for significant cost savings.

Rogue Wave helps thousands of global enterprise customers tackle the hardest and most complex issues in building, connecting, and securing applications. Since 1989, our platforms, tools, components, and support have been used across financial services, technology, healthcare, government, entertainment, and manufacturing, to deliver value and reduce risk. From API management, web and mobile, embeddable analytics, static and dynamic analysis to open source support, we have the software essentials to innovate with confidence. @2018 Rogue Wave Software, Inc. All rights reserved.