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Physical Ports Missing from "ip link show" Output - switchd Failure




ip link show displays only the loopback and management (ethX) ports. Physical switch ports — the interfaces starting with swp — are not visible to the operating system.

$ sudo ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN mode DEFAULT 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000
    link/ether 44:38:39:00:25:d7 brd ff:ff:ff:ff:ff:ff


  • Cumulus Linux, all versions


The switchd daemon is responsible for setting up the physical ports. When switchd fails to start, the physical ports are not visible to the operating system.


Typically, switchd fails to start when the Cumulus Linux license is missing.

If your license is installed and switchd still fails to start, capture any errors that may occur and generate the cl-support files, then send them to the Cumulus Networks support team.

Follow the appropriate steps below.

If the Cumulus Linux License Is not Installed

If a valid license is not installed, the physical ports will not come up. Verify that a license is installed using the command cl-license.

$ sudo cl-license
No license installed!

Contact the Cumulus Networks support team to obtain a license.

switchd Fails to Start with the Error: Syntax error parsing "thdi_input_port_xon_enables.xe0-xe127"

This error occurs when the port capacity configured on the switch exceeds the capability of the ASIC. Read the heading in the /etc/cumulus/ports.conf file for details on how to configure the ports.conf file. If the header is missing, run the cl-img-clear-overlay command to restore the switch back to its original configuration. Make sure to remove the /mnt/persist/etc/cumulus/ports.conf file if it exists.

Error: "No attached units. BDE found 0 switch devices."

An error like this indicates the kernel can't find the Broadcom ASIC. After you manually start the switchd service using the service switchd start command, check the /var/log/switchd.log for the following error:

Platform: Cumulus_Networks_LLC
OS: Unix (Posix)
Boot flags: Cold boot
No attached units.
BDE found 0 switch device(s)
1421276331.445789 2014-01-11 10:33:51 hal.c:169 CRIT No backends found.
1421276331.445857 2014-01-11 10:33:51 switchd.c:632 Switchd exiting.

If you see the above error, confirm that the Broadcom ASIC is not seen by the kernel by running the lspci -v command. Look for the following output:

01:00.0 Ethernet controller: Broadcom Corporation Device b850 (rev 03) 
Subsystem: Broadcom Corporation Device b850
Flags: bus master, fast devsel, latency 0, IRQ 21
Memory at ff600000 (64-bit, non-prefetchable) [size=256K]
Capabilities: [48] Power Management version 3
Capabilities: [50] Vital Product Data
Capabilities: [58] MSI: Enable- Count=1/1 Maskable- 64bit+
Capabilities: [ac] Express Endpoint, MSI 00
Kernel driver in use: linux-kernel-bde

If the above output is missing, replace the switch.

If switchd Fails to Start for Another Reason

Manually start the switchd service using the service switchd start command. Root/sudo access is required. If an error occurs:

  1. Save the entire error message.
  2. Download any Cumulus Linux support files. The support files are located in /var/support/core.
  3. Open a case with Cumulus Support and upload the above information.
$ sudo service switchd restart

can not execute decode-syseeprom
.py", line 544, in check_output
raise CalledProcessError(retcode, cmd, output=output)
subprocess.CalledProcessError: Command '('/usr/cumulus/bin/decode-syseeprom', '-r')' returned non-zero exit status 1
-m requires a MAC address as an argument
usage: /usr/sbin/switchd [-n] [-d] [-V] [-L BACKEND=LEVEL [BACKEND=LEVEL]] [-t TABLE_NUM] [-s]


This support portal has moved

Cumulus Networks is now part of the NVIDIA Networking Business Unit! The NVIDIA Cumulus Global Support Services (GSS) team has merged its operations with the NVIDIA Mellanox support services team.

You can access NVIDIA Cumulus support content from the Mellanox support portal.

You open and update new cases on the Mellanox support portal. Any previous cases that have been closed have been migrated to the Mellanox support portal.

Cases that are still open on the Cumulus portal will continue to be managed on the Cumulus portal. Once these cases close, they will be moved to the Mellanox support portal.

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