Consider the following five points when performing firmware upgrades, not only in FortiOS but in general. This applies to pretty much any change you have to do in a production environment.
Before attempting any changes in production, first make sure you set up a laboratory where you can freely play with the new features, and understand them with enough time and no pressure. Read the Release Notes, Manuals, and other documentation like presentations, videos, or podcasts about the new version.
You are ready to explain the need for an upgrade once you understand:
- The differences and the enhancements between the new version and the previous version(s).
- The impact of the upgrade on customers and the users of the operating platform.
- The known limitations that might affect your environment.
- The potential risks when performing the upgrade.
- The licensing changes that may apply.
Never attempt to upgrade to a version that you do not fully understand (both on features and known limitations), and on which you have no operational experience.
The reason can NOT be “Because I want to have the latest version”. The reason has to be explained in terms of business, technical, and/or operational improvement.
Affirmative answers to the following questions are valid reasons to upgrade:
- Does the new version have a feature that helps to ensure compliance?
- Does the new version have an enhancement that allows 40% decrease (40% improvement) on the time to perform a certain operation?
- Does the new feature correct a known defect/bug found on a previous version that affects the company business/operations?
- Will the new version allow your organization to deploy new services that will help to gain new customers or increase loyalty of existing ones?
- Is the vendor cutting support for the version your organization is currently using?
If the best reason to upgrade is “Because the new features seem to be cool” or “Because I want to have the latest version”, a little more understanding and planning may be necessary.
If you choose to upgrade because you found a valid reason to do so, make sure you create a plan that covers business, technical, and operational aspects of the upgrade:
Proper planning and justification for an upgrade should be proportional to how critical the system is to the business.
- Make sure you can clearly articulate the benefits of the upgrade in business terms (time, money, and efficiency).
- Understand the business processes that will be affected by the change.
- Make sure the upgrade maintenance window is not close to a business-critical process (such as quarterly or monthly business closure).
- Obtain executive and operational approval for the maintenance window. The approval must come from the owners of ALL the systems/information affected by the upgrade, not only from those that own the system being upgraded. The approval must be done in a formal (written or e-mail) form.
- Re-read the Release Notes for the technology you are upgrading. Supported hardware models, upgrade paths, and known limitations should be clearly understood.
- Make sure your upgrade maintenance window does not overlap with any other maintenance window on your infrastructure.
- If you have any premium support offer (such as TAM, Premium Support), do a capacity planning exercise to ensure the new firmware/software version does not take more hardware resources than you currently have.
- Create a backup, whether or not you have scheduled backups. Create a new fresh backup.
- Obtain offline copies of both the currently installed firmware and the new version.
- Create a list of systems with inter-dependencies to the system you are upgrading. For example, if you are upgrading a FortiGate; understand the impact on any FortiAP, FortiAuthenticator, FortiToken, FortiManager, or FortiAnalyzer you have on your environment.
- Ensure you have a list of adjacent devices to the upgrading platform and have administrative access to them, just in case you need to do some troubleshooting. Are you upgrading FortiWeb? Make sure you can administratively access the Web Applications. Are you upgrading a FortiGate? Make sure you can administratively access the surrounding switches and routers.
- Have a step-by-step plan on how to perform and test the upgrade. You want to make sure you think of the worst situation before it happens, and have predefined courses of action, instead of thinking under pressure when something already went wrong.
- Define a set of tests (that include critical business applications that should be working) to make sure the upgrade went fine. If any test does not go well, define which ones mandate a rollback and which ones can be tolerated for further troubleshooting. This set of tests should be run before and after the upgrade to compare results, and they should be the same.
- Define a clear rollback plan. If something goes wrong with the upgrade or the tests, the rollback plan will help you get your environment back to a known and operational status. The plan must clearly state the conditions under which the rollback will be started.
- Declare configuration freezes. A little bit before and after the upgrade. The idea is to reduce the amount of variables to take into consideration if something goes wrong.
- Perform a “Quality Assurance” upgrade. Grab a copy of the production configuration, load it on a non-production box and execute the upgrade there to see if there are any issues on the process. Then adjust your plan according to the results you obtained.
- Have a list of information elements to be gathered if something goes wrong. This ensures that, even if the upgrade fails, you will collect enough information so you can troubleshoot the issue without needing to repeat the problem. Get help from Fortinet Support if you need to check what else could be missing on your list.
- Define a test monitoring period after the change was completed. Even if the upgrade went smoothly, something could still go wrong. Make sure you monitor the upgraded system for at least one business cycle. Business cycles may be a week, a month, or a quarter, depending on your organization’s business priorities.
Execution of an upgrade is just as key as planning.
Once you are performing the upgrade, the pressure will rise and stress might peak. This is why you should stick to the plan you created with a cool head.
Resist the temptation to take decisions while performing the upgrade, as your judgment will be clouded by the stress of the moment, even if a new decision seems to be “obvious” at such time. If your plan says you should rollback, then execute the rollback despite the potential “We-can-fix-this-very-quickly” mentality.
While performing the upgrade, make sure all the involved components are permanently monitored before, during, and after the upgrade, either via monitoring systems, SNMP alerts, or at least with tools like a ping. Critical resources like CPU, memory, network, and/or disk utilization must also be constantly monitored.
To avoid misunderstandings, when performing the tests for each critical application defined on the planning, make sure there are formal notifications on the results for each user area, service, system, and/or application tested.
Regardless if you have to rollback or not, if a problem occurs, make sure you gather as much information about the problem as possible, so you can later place a Support ticket to find a solution.
Last but not least, document the upgrade:
- Enable your terminal emulation program to leave trace of all the commands executed and all the output generated. If you are performing steps via GUI, consider using a video capture tool to document it.
- Document any command or change performed over the adjacent/interdependent systems. Make sure they are acknowledged by the relevant administrators
- Document any deviations performed over the upgrade plan. This is planned-versus-actual.
Change Management and Change Control are huge knowledge areas in the field of Information Systems and Computer/Network Security.
This document is by no means a comprehensive list on what you should do when performing an upgrade, with either Fortinet or any other technology. It is merely a list of important things you should take into consideration when performing upgrades which are the result of years of experience dealing with changes on critical environments, as it is common that security devices are protecting critical applications and processes.
There are vast resources on the topic: books, public white papers, blog entries, etc. If you search the Internet for the “Change Control Best Practices” or “Change Management Best Practices” you will get many interesting documents.
|Changes on production IT infrastructure are critical to the business. Make sure they play in your favor and not against you.|