Communications failure with Cisco Smart License server
Impact
Device retries connecting later once DNS is addressed.
Description
This error appears if there is Smart Licensing configured on the device.
Smart Licensing is a cloud-based unified license management system for managing licenses across Cisco products.
Depending on your network type and setup, you could be using different methods of communication with the CSSM (Cisco Smart Software Manager) portal.
These errors appear if you are using a CSLU or an On-Prem method and there is a communication issue between device and server. It can be related to a DNS lookup issue or a configuration issue.
%SMART_LIC-3-COMM_FAILED: Communications failure with the Cisco Smart License Utility (CSLU) : Unable to resolve server hostname/domain name.
Sometimes this error can also appear if the device booting up after a reload or an upgrade. If the device registers correctly with the portal once it books up, the this error can be ignored. Please check Remediation steps to resolve this
SyslogMessage
%SMART_LIC-3-COMM_FAILED
MessageSample
Apr 10 10:10:10 <> %SMART_LIC-3-COMM_FAILED: Communications failure with the Cisco Smart License Utility (CSLU) : Unable to resolve server hostname/domain name THIS IS A SAMPLE MESSAGE
ProductFamily
- Cisco Catalyst 9200 Series Switches
- Cisco Catalyst 9300 Series Switches
- Cisco Catalyst 9400 Series Switches
- Cisco Catalyst 9500 Series Switches
- Cisco Catalyst 9500H Series Switches
- Cisco Catalyst 9600 Series Switches
Regex
N/A
Recommendation
Verify that device can ping the CSLU IP address If domain names are being used for communication, ensure DNS server is configured correctly.
You need to specify the correct "source-interface" that you are using for communicating with the CSSM portal.
Command: Switch(config)#ip name-server Switch(config)#ip domain-lookup [source-interface]
If this is a VRF set-up, use these commands (depending on the VRF being used):
(config)#ip domain-lookup [source-interface ] <<-- "ip vrf forwarding " defined on the interface (config)#ip name-server vrf
Verify that the HTTPs client source-interface is defined for the correct interface.
Command: ip http client source-interface
If VRF is used, use this command:
Command: Switch(config)#ip http client source-interface
Ensure the transport mode for Smart licensing is set to cslu:
Command: Switch(config)# license smart transport cslu
Verify the correct CSLU IP/Hostname is confgured as per the URL:
URL: http://:8182/cslu/v1/pi
Note: The default URL is configured for "cslu-local" to enable automatic discovery.
IF you want to use this option, configure the name server with an entry where hostname cslu-local is mapped to the CSLU IP address (the windows host where you installed CSLU), no other configuration is required.
The product instance automatically discovers hostname cslu-local. If all the previous configurations are verified and correct, you can manually initiate a license sync with CSLU via the command "license smart sync all".
This causes the device to manually attempt a re-sync with the CSLU utility. With the releases of Cisco IOS XE 17.3.2 and 17.4.1 and higher, Smart Licensing using Policy was introduced.
So if you started seeing the errors after a recent upgrade to these codes, then please refer to the Migration Document that explains the different options:
https://www.cisco.com/c/en/us/support/docs/switches/catalyst-9300-series-switches/216520-migrate-catalyst-license-to-smart-licens.html
Commands
#show version
#show logging
#show license all
#show license summary
#show call-home profile all
#show tech-support license
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