What's New

This document supports the Cumulus Linux 5.19 release, and lists new features and enhancements.

• For a list of open and fixed issues in Cumulus Linux 5.19, see the Cumulus Linux 5.19 Release Notes.
• To upgrade to Cumulus Linux 5.19, first check the Release Considerations below, then follow the steps in Upgrading Cumulus Linux.

What’s New in Cumulus Linux 5.19.0

Cumulus Linux 5.19.0 supports new platforms, contains new features and improvements, and provides bug fixes.

Platforms

• NVIDIA SN6600 (128x800G Spectrum-6)
• NVIDIA SN4700 (Spectrum-3)

New Features and Enhancements

• Prevent re-export of VRF-leaked EVPN routes
• Class E (240.0.0.0/4) address space support
• Disjoined multiplane support for EVPN unreachability with 802.1X dynamic VRF assignment
• Layer 3 VXLAN device mode is generally available
• Multi ASIC fast boot support (Beta)
• Full resource mode ISSU on Spectrum-4 and later switches (Beta)
• BFD offload to switch firmware
• Control plane punt classifier drop counters
• The cl-support file captures the SSD internal NAND debug log on a switch with a Virtium NVMe SSD
• Patch uninstall returns the switch to the patch installed underneath, and a new command reclaims the space held by superseded patches
• PFC watchdog detection parameters that distinguish a real deadlock from steady-state congestion
• Security configuration visibility for manufacturing and field inspection
• Back-to-sender notification when an MRC egress link fails
• Adaptive routing extended grading on Spectrum-6 switches
• Step time estimation for AI training workloads
• Adaptive routing ECMP group segregation for round-robin port selection on Spectrum-6 switches
• Dedicated service port ingress buffers on Spectrum-6 switches
• Adaptive routing hybrid scheduling mode, which moves low weight ECMP groups to random forwarding to reduce adaptive routing group merging
• FRR upgrade phase 5
• VRF per destination support GA - at risk
• Loopback IP/Interface as Source for NVUE DNS in Cumulus Linux 5.x
• Change the USB0 IP address to 169.254.100.2 / 169.254.100.1
• CPO Debug Params | nv show commands & Telemetry (OTEL and GNMI) GA
• NVUE
  • Switch power off command
  • Clear a stale IPv6 ND prefix on demand
  • Manage staged platform firmware files, automatic updates, and firmware source per component
  • Show and install transceiver firmware
  • IPv6-only unnumbered peering command
  • Resilient hashing commands
  • nv config apply command improvements to prevent latency and timeout
  • Suppress ZTP console messages
  • Map port to connector
  • Configure the file descriptor limit for the FRR routing daemons
• Telemetry
  • WJH metrics for OTEL
  • gNMI component type and name for platform components
  • gNMI and OTEL metrics for unreachability AFI SAFI
  • gNMI metrics for AAA RADIUS
  • Microburst histogram with per-port burst scoring

Release Considerations

Review the following considerations before you upgrade to Cumulus Linux 5.19.

Upgrade Requirements

You can use optimized image upgrade and package upgrade to upgrade the switch to Cumulus Linux 5.19 from the following releases. Package upgrade supports ISSU (warm boot) for these upgrade paths.

• 5.16.1 through 5.16.7
• 5.17.0
• 5.18.0

To upgrade to Cumulus Linux 5.19 from a release that does not support package upgrade or optimized image upgrade, you can install an image with ONIE.

For a list of the earliest Cumulus Linux releases supported for each switch model, refer to this knowledge base article.

Linux Configuration Files Overwritten

If you use Linux commands to configure the switch, read the following information before you upgrade to Cumulus Linux 5.19.

NVUE includes a default startup.yaml file. In addition, NVUE enables configuration auto save by default. As a result, NVUE overwrites any manual changes to Linux configuration files on the switch when the switch reboots after upgrade, or you change the cumulus user account password with the Linux passwd command.

To prevent Cumulus Linux from overwriting manual changes to the Linux configuration files when the switch reboots or when changing the cumulus user account password with the passwd command, follow the steps below before you upgrade to 5.19 or after a new binary image installation:

1. Disable NVUE auto save:

cumulus@switch:~$ nv set system config auto-save state disabled
cumulus@switch:~$ nv config apply
cumulus@switch:~$ nv config save

2. Delete the /etc/nvue.d/startup.yaml file:

   cumulus@switch:~$ sudo rm -rf /etc/nvue.d/startup.yaml
   

3. Add the PASSWORD_NVUE_SYNC=no line to the /etc/default/nvued file:

   cumulus@switch:~$ sudo nano /etc/default/nvued
   PASSWORD_NVUE_SYNC=no
   

DHCP Lease with the host-name Option

When a Cumulus Linux switch with NVUE enabled receives a DHCP lease containing the host-name option, it ignores the received hostname and does not apply it. For details, see this knowledge base article.

NVUE Commands After Upgrade

After you upgrade to Cumulus Linux, running NVUE configuration commands might override configuration for features that are now configurable with NVUE and removes configuration you added manually to files or with automation tools like Ansible, Chef, or Puppet. To keep your configuration, you can do one of the following:

• Update your automation tools to use NVUE.
• Configure NVUE to ignore certain underlying Linux files when applying configuration changes.
• Use Linux and FRR (vtysh) commands instead of NVUE for all switch configuration.

nv show vrf <vrf-id> router bgp address-family <address-family>-unreachability route -o json Command

In Cumulus Linux 5.18 and later, running the nv show vrf <vrf-id> router bgp address-family <address-family>-unreachability route -o json command is now equivalent to running the vtysh show bgp vrf <vrf-id> ipv6 unreachability json brief command. Therefore, certain fields, such as path details and reporter AS, no longer show. To show a more detailed view, run the nv show vrf <vrf-id> router bgp address-family <address-family>-unreachability route <prefix> -o json command.

BFD Offload Configuration and Show Output

Cumulus Linux 5.19 replaces the BFD offload boolean with an offload mode that selects where BFD packet processing runs; see BFD Offload.

• The nv set router bfd offload <enabled|disabled> command is replaced by nv set router bfd offload-mode <control-plane|kernel|hardware>. When you upgrade, Cumulus Linux translates offload enabled to offload-mode kernel and removes offload disabled, which leaves the control-plane default in effect.
• The per-peer offload field now reports the engine carrying the session. In nv show vrf <vrf-id> router bfd peers output, the Offloaded column shows kernel, hardware, or control-plane; in vtysh and JSON output, offload-status shows the same three values. In Cumulus Linux 5.18 and earlier, this field shows only offloaded or control-plane. Update any automation or monitoring that matches on the string offloaded.

Cumulus VX

NVIDIA no longer releases Cumulus VX as a standalone image. To simulate a Cumulus Linux switch, use NVIDIA DSX Air.