Fortinet Firmware Parallel development and Upgrading Methods

Parallel development

Firmware development is usually occurring on two paths at the same time. Development takes place on the latest path, as well as the previous stable path. For example, if the latest path is 5.0.x, then the previous stable path that would still be in development would be 4.3.x. This has two significant ramifications as far as upgrades are concerned. The first is that patches are still built for each of these paths. The second is that because this development takes place in parallel, the number identifiers for the builds do not correspond directly with the sequence in which the builds come out.

Occasionally, it appears as if there are some odd jumps in the upgrade sequence. This has to do with the timing of releases of different firmware versions. Later builds of different versions can come out close together and therefore have a high likelihood of compatibility. This is why you can only upgrade 5.0.6 only to 5.0.9 but you can upgrade 4.3.18 all the way to 5.0.12.

Upgrade methods

1. from a local file that has been previously downloaded

2. from the FortiGuard Network.

Upgrading from the local drive

When uploading the firmware from the local drive, you must already have downloaded it from the Fortinet Support Site. After you log in with the account ID and password that was created when registering the FortiGate, go to the Download section and select the icon for Firmware images. From there it is only a matter of selecting a product, such as a FortiGate and then selecting either HTTPS or FTP download. The layout of the firmware listing in both methods is a hierarchical tree. For instance, if you wanted firmware 5.0.7 you would select the v5.00 directory, then the 5.0 directory, then the 5.0.7 directory. Once in the directory scroll down until you find the correct firmware file name for your specific model. Then select the file you wish to download.

The file names are intended to be helpful in determining the correct firmware for the model you need. Here are some of the conventions found in the file names.

FGT_ = FortiGate
FWF_ = FortiWiFi
POE = Power over Ethernet
VM32/VM64 = Virtual Machine versions of the firmware. The 32 and 64 referring to the bit architecture of the OS.
Firmware going directly to a Fortinet Device will have the .out extension.

Upgrading from the FortiGuard Network

The practice of strategically skipping some firmware versions to optimize the time and efficiency that it takes to get to the latest version is based on using the Upgrade from: Local Hard Drive option. If you try to use the Upgrade from: FortiGuard Network option you will notice that there is a limited number of firmware builds to which you may upgrade or downgrade. This is because only options that are always going to be safe are available. The logic being that because there are no intermediate options possible, the next consecutive build will always be a safe option.

Because of this limitation in options, you will not be able to use the Upgrade from: FortiGuard Network option to see all of the safe upgrade options. You will either have to use the included upgrade path table or study the Release Notes.

The builds that will be shown will most like be as follows:

For Upgrades:

The next build in the current version track

For Downgrades:

The previous build in the current version track.

The latest build in the previous version track.