Troubleshooting Log Files
The only real unique entity for logging on Cumulus Linux compared to any other Linux distribution is switchd.log, which logs the HAL (hardware abstraction layer) from hardware.
Read this guide on NixCraft to understand how /var/log works.
Log File Descriptions
| Log | Description |
|---|---|
/var/log/alternatives.log | Information from update-alternatives. |
/var/log/apt | Information from the apt utility. For example, from apt-get install and apt-get remove. |
/var/log/audit/* | Information stored by the Linux audit daemon, auditd. |
/var/log/autoprovision | Output generated by running the zero touch provisioning script (ZTP). |
/var/log/boot.log | Information that the system logs when the switch boots. |
/var/log/btmp | Information about failed login attempts. Use the last command to view the btmp file. For example:cumulus@switch:~$ last -f /var/log/btmp | more |
/var/log/clagd.log | Status of the clagd service. |
/var/log/dpkg.log | Information that the system logs when you install or remove a package with the dpkg command. |
/var/log/frr/* | FRR - Used to troubleshoots routing, such as an MD5 or MTU mismatch with OSPF. |
/var/log/gunicorn | Error and access events in Gunicorn. |
/var/log/installer/* | Directory containing files related to the installation of Cumulus Linux. |
/var/log/lastlog | Formats and prints the contents of the last login log file. |
/var/log/nvued.log | Log file for NVUE. |
/var/log/nginx | Errors and processed requests in NGINX. |
/var/log/ntpstats | Logs for network configuration protocol. |
/var/log/openvswitch/* | ovsdb-server logs. |
/var/log/ptmd | Prescriptive Topology Manager (PTM) errors and information. |
/var/log/switchd.log | The HAL log for Cumulus Linux. This is specific to Cumulus Linux. The system logs switchd crashes here. |
/var/log/syslog | The main system log, which logs everything except auth-related messages. The primary log; grep this file to see what problem occurred. |
/var/log/wtmp | Login records file. |