What is NOS?

At Meter, firmware for each hardware platform is tested and released together in a unified image, called the Network Operating System (NOS).

How is a new NOS version rolled out?

NOS is updated at a regular cadence, generally every 2-3 months. The upgrade will always occur during the network's defined maintenance window, unless there are special circumstances. Instructions to check or update a network’s maintenance window can be found here: Settings > How to View / Update Network's Maintenance Window.

Devices are upgraded in groups. The order is typically: 

1. Power Distribution Units
2. ISP switches
3.  Security Appliance(s)
4. Core Switches
5. Distribution Switches
6. Access Switches
7. Access Points

After each group completes its update, there is a 5-10 minute wait time until the next group of devices begins. This is to ensure network stability and to halt the upgrade should an issue arise.

Meter gradually rolls out NOS versions across the entire fleet spanning a period of weeks. Small groups of networks are upgraded initially. Over the release cycle, larger and larger groups of networks are upgraded until the entire fleet is on the new NOS version.

How are NOS versions tested?

In addition to Meter’s QA team putting each NOS version through rounds of testing, new NOS versions are deployed to internal Meter networks (called Dogfood networks). Beta testing is also completed by Meter Partners.

Who can push NOS updates?

Meter is solely responsible for NOS rollouts across the fleet.

Release Notes

NOS-10.2 to NOS-10.6 (May 2025)

Bug Fixes and Improvements

Security Appliances

• General performance and stability improvements
• Improved Multi-WAN Round Robin behavior for more reliable session handling, including graceful TCP resets on route expiration and enhanced NAT session management

Access Points

• General performance and stability improvements
• DHCP event logs are now visible on the Dashboard’s Connection Events page
• Improved handling of ARP traffic in networks with a high number of Access Points and clients

Switches

• General performance and stability improvements

NOS-9 to NOS-10.2 (March 2025)

Bug Fixes and Improvements

NOS 10 contains many improvements and fixes, including: Security Appliances

• Improved performance for networks with hundreds of VLANs
• Improved MultiWAN round robin reliability
• Improved policy routing reliability
• Improved handling of DNS over TCP
• Fix for port-forward conflicts with IPSec tunnel ports
• Fix for stability issues caused when multiple clients use the same WireGuard configuration

Access Points

• Added DHCP event failure logs
• Fix for WPA3 client roaming failures caused by inconsistent association state handling
• Improved stability during firmware upgrades

Switches

• Improved resilience against issues caused by port flapping from bad ports, cables, and SFP issues
• Improved stability during firmware upgrades

New Features

The following features have firmware support in this NOS release. The features will progressively become available in the next few months. Please reach out to your CSM if you’re interested in piloting any of them:

Security Appliances

• High availability
• Rate Limiting Per Source

Access Points

• Client Isolation
• SSID Scheduling
• AP Health Scores
• Proxy ARP
• Wireless Packet Captures

Switches

• Port rate limiting
• Port isolation
• Port Security with MAC Limiting
• Manual MTU Configuration