Common Log Files for Troubleshooting

This page provides a comprehensive list of important log file paths in Ubuntu Server environments commonly used at Voltage Park.

Log Type	Log Path
System Log	`/var/log/syslog`
Kernel Log	`/var/log/kern.log`
Boot Log (dmesg)	`/var/log/dmesg`
Authentication Log	`/var/log/auth.log`
NVIDIA Installer Log	`/var/log/nvidia-installer.log`
Slurm Controller Log	`/var/log/slurm/slurmctld.log`
Slurm Node Daemon Log	`/var/log/slurm/slurmd.log`
Docker Log	`/var/log/docker.log`
NFS Logs	`/var/log/messages`, `/var/log/syslog`
NGINX Access Log	`/var/log/nginx/access.log`
NGINX Error Log	`/var/log/nginx/error.log`
Apache Access Log	`/var/log/apache2/access.log`
Apache Error Log	`/var/log/apache2/error.log`
MySQL / MariaDB Error Log	`/var/log/mysql/error.log`
PostgreSQL Log	`/var/log/postgresql/postgresql-<version>-main.log`
UFW Log	`/var/log/ufw.log`
Fail2Ban Log	`/var/log/fail2ban.log`
APT History Log	`/var/log/apt/history.log`

How to Access and Read Log Files

Logs are essential for troubleshooting issues in a server environment. You can access log files using the command line in Ubuntu. Most of these logs are located in the /var/log/ directory. Below are a few common commands to access and read log files:

View Logs in Real-Time: Use tail -f to follow the most recent updates in a log file:
```
sudo tail -f /var/log/syslog
```
View Entire Log File: Use cat to display the entire contents of a log file:
```
sudo cat /var/log/kern.log
```
Search for Specific Terms: Use grep to filter log entries for a specific keyword:
```
sudo grep "error" /var/log/syslog
```
View Compressed Logs: Archived logs are often compressed with .gz. You can use zcat to read them (may need installing with apt-get install:
```
sudo zcat /var/log/syslog.1.gz
```