System Logs
Logging to a remote server
The Cisco Nexus 3550-H Hydra (formerly ExaLINK Hydra) supports remote logging using the syslog protocol.
To configure remote logging, use the logging command.
The first step is to configure a remote target for log messages.
Both TCP and UDP modes of syslog are supported. As an example, to log all
error messages using UDP to a host at 192.168.220.13, use the command:
admin@EXALINK-HYDRA# configure logging host 192.168.220.13 protocol udp
Enabled remote logging to 192.168.220.13 using UDP
To remove all remote logging targets use the no form of the logging command:
admin@EXALINK-HYDRA# configure no logging host 0.0.0.0 protocol udp
Disabled remote logging to 0.0.0.0 using UDP
To change the global remote logging level, users may configure the trap
admin@EXALINK-HYDRA# configure logging trap error
Set remote logging level to 3 (error)
Audit logs
When remote logging is configured, the Nexus 3550-H will also send an audit log of configuration changes to the remote syslog server.
Configuration change logging is done at the API layer. Because commands on the command line are internally implemented using the API, this captures all configuration changes from the command line as well as from the API.
Example configuration change message:
Oct 1 11:27:26 EXALINK-HYDRA AUDIT: { "username": "admin", "method": "set_interface_enable", "params": { "interface": "ethernet1\/1", "enable": true }, "result": true }
Each message contains the details of an API command encoded in JSON format with the following fields:
| Field | Description |
|---|---|
| username | User that made the change |
| method | Name of API command |
| params | API parameters |
| result | Result of API command |
| error | Error code and message |
The error field will not be present if the API command was successful.
Similarly, the result field will not be present if the API command failed.
Please see the API documentation for details of the API commands.
Viewing system logs locally
From bash users may view local logs via the standard Unix utility journalctl.
admin@EXALINK-HYDRA# bash
admin@EXALINK-HYDRA~$ journalctl
-- Logs begin at Mon 2019-05-06 23:16:58 UTC, end at Tue 2019-05-07 03:31:29 UTC. --
May 06 23:16:58 localhost kernel: Linux version 4.9.0-9-amd64 (debian-kernel@lists.debian.org) (gcc version 6.3.0 20170516 (Debian 6.3.0-18+deb9u1) ) #1 SMP Debian 4.9.168-1 (2019-04-12)
...
Note
Audit log messages cannot be viewed using journalctl.
Only system log messages are available.
This page was last updated on Feb-18-2021.