Tag Archives: Cumulus Linux

How to Upgrade Cumulus Linux on N-Series Switches?


Before Upgrading Cumulus Linux

Before any update, you should consider the migration and backup of some important data or files in case of any accident or emergency. In that way, being clear about the location of your configuration data is crucial before updating Cumulus Linux. Just like other Linux operating system distributions, the /etc directory is the primary location for all configuration data in Cumulus Linux. In the following figures, we list some files and as well as their directories that you are likely to do the backup.

Cumulus Linux Network Configuration Files

Figure 1: Cumulus Linux Network Configuration Files

Additional Commonly Used Files

Figure 2: Additional Commonly Used Files

Note: If you are using the root user account, consider including /root/. If you have custom user accounts, consider including /home//.

Upgrading Processes

Basically, there are two methods to upgrade Cumulus Linux: disk image install and package upgrade. According to different environment and preferences, the upgrade can be achieved in different ways. In this part, we will guide you on how to use these two ways one by one. By the way, if you are using MLAG to dual connect two switches in your environment, there are additional steps to follow. You can refer to the guide：Upgrade Switches in an MLAG Pair.

Solution 1: Installing A Disk Image

When you are performing a rolling upgrade in a production environment and using up-to-date and comprehensive automation scripts, the disk image installation will be recommended. It enables you to choose the exact release to which you want to upgrade. Moreover, it is the only method available to upgrade your switch like a 10GbE switch to a new release train (for example, from 2.5.6 to 3.7.0) or from a release earlier than 3.6.2.
To apply this upgrade, you need to use ONIE (open network install environment), which allows the installation of network operating systems (NOS) on a bare metal switch. FS N-series switches all include an ONIE installer. There are mainly six steps you can follow with:

1. Back up the configurations off the switch.

2. Download the Cumulus Linux image you want to install.

3. Install the disk image with the onie-install -a -i command, which boots the switch into ONIE. There are various ways to install the disk image, such as using FTP, a local file, or a USB drive. In figure 3, we demonstrate how to install image from a web server as your reference. After disk image installed, the switch can be rebooted.

Disk Image Install

Figure 3: Disk Image Install

4. Restore the configuration files to the new release—ideally with automation.

5. Verify correct operation with the old configurations on the new release.

6. Re-install third-party applications and associated configurations.

Solution 2: Upgrading Packages

Package upgrade is recommended if you are upgrading from Cumulus Linux 3.6.2 or later, or if you use third-party applications (package upgrade does not replace or remove third-party applications, unlike disk image install). When upgrading, configuration data stays in place. If the new release updates a configuration file that you changed previously, you are prompted for the version you want to use or if you want to evaluate the differences. Altogether, there are six steps as follows:

1. Back up the configurations from the switch.

2. Apply the following command to fetch the latest update metadata from the repository.

Command for the Latest Update Metadata

3. Review potential upgrade issues (in some cases, upgrading new packages might also upgrade additional existing packages due to dependencies). Run the following command to see the additional packages that will be installed or upgraded.

Command for Additional Packages

4. Upgrade all the packages to the latest distribution.

Command to the Latest Distribution

5. Reboot the switch if the upgrade messages indicate that a system restart is required.

Command to Reboot the Switch

6. Verify correct operation with the old configurations on the new version.

Questions & Answers

Besides the procedures to upgrade Cumulus Linux, we also list some questions concerned most by our FS customers.

1. How to Deal With Upgrade Failures?

Even the most well planned and tested upgrades can result in unforeseen problems. If you fail to upgrade Cumulus Linux, sometimes the best solution is to roll back to the previous state. You can refer to the following three techniques:

  • Back out individual packages: If you identify the problematic package, you can downgrade the affected package directly. In rare cases, you might need to restore the configuration files from backup or edit to back out any changes made automatically by the upgrade package.
  • Flatten and rebuild: use orchestration tools to re-install the previous OS release from scratch and then rebuild the configuration automatically.
  • Backup and restore: restore to a previous state, using a backup captured before the upgrade.
2. Will Future Software Updates for Cumulus Linux Be Free?

For FS N-series switches, the default validity of Cumulus Linux is one year. If Cumulus Linux OS is upgraded after 1 year, the customer can’t upgrade it for free and needs to renew the software support. Even if the software support service has been expired, you are allowed to use your current software as usual. By the way, we also provide a three-year software support fee option and a five-year software support fee option. The longer for OS support you choose, the more economical the switch will be.

3. Who Will Cover Technical Support?

FS will provide five-year tech support for the hardware. As for the problems about Cumulus Linux, FS and Cumulus will solve it together. Moreover, as one of the Linux distributions, the source code of Cumulus Linux is also freely available to everyone to use, modify or share such as GitHub. Just like the above question about the software update, the default validity of technical support for Cumulus Linux is one year. One year later, you can renew the support term.


In this post, we mainly focus on how to upgrade the Cumulus Linux on FS N-series switches. In addition, we list three after-sales related questions frequently asked by our FS customers.

Open Switch—One Contributor to Open Source Network


What Is Open Switch?

Open switches refer to switches in which the hardware and software are separate components that can be changed independently of each other. That means you will gain more flexibility to tailor your own network switch. Conventionally, the open source switch in the market can mainly be classified into the bare metal switch, white box switch, and brite box switch.

Open Switch

Figure 1：Open Switch

Open Switch Hardware

The open hardware means the hardware of an open switch can support multiple operating systems (OS). This is in contrast to closed switches, in which the hardware and software are always purchased together. For example, if you buy a Juniper EX or MX you also buy JUNOS; if you buy a Cisco Catalyst switch you buy IOS. However, things will be different with open switches. In the context of that, no matter which type of open source switch you are using, it’s possible to support many operating systems instead of a proprietary one. By the way, the hardware manufacturers of the open switch are primarily Taiwanese, including Accton, Quanta QCT, Alpha Networks, and Delta Computer. These same companies are original design manufacturers (ODMs) for many of the mainstream switch vendors.

Open Hardware

Figure 2: Open Hardware

Open Switch Software

The open software signifies that an OS can be run on multiple hardware configurations. As we mentioned before, you don’t need to buy an OS from the original brand of your switch hardware. For example, if you have Cumulus Linux, you can buy a layer 3 switch without a brand label. They still work well with each other. In the past, most people have no choice but to use brite box switch that integrates OS and hardware of branded suppliers. Now, with an open switch software, choices and economic efficiency will be largely expanded and improved. Generally, there are three popular open softwares in the market: Cumulus Linux, IP Infusion OcNOS and Pica8 PICOS.

Cumulus Linux Software

Figure 3: Cumulus Linux Software

Why Choose Open Switch?

  • With an open source switch, more flexibility, and options can be enjoyed. There is no need to configure your switch as in the past or wait for vendors to release new software or hardware.
  • It brings the open source network to operators, enterprises, third-party vendors and network users, accelerates the innovation speed of new services and functions of the network deployment, and takes users closer to SDN (software-defined network) and NFV (network functions virtualization).
  • The network simplicity and reliability can be improved through the automated centralized network device management, unified deployment strategies, and fewer configuration errors.
  • The network flexibility and scalability have been greatly increased, which will also save much cost and time for IT workers and enterprises.


In this post, we make an exploration of the open switch. From the introduction to its hardware, software, and benefits, we can understand why the open switch has been a great facilitator for open networking.