# Multiline Log Records in Syslog

Handling multiline log records in `rsyslog` can be a bit tricky, as it is designed primarily to handle single-line messages. However, you can configure `rsyslog` to process multiline logs by setting up specific rules in your configuration. Here’s a general approach to handle multiline log records:

1. **Define a Custom Template for Multiline Logs**:
You need to define a template that will handle multiline log entries correctly. This template should specify how to concatenate multiple lines into a single message.
2. **Set Up the Input Module**:
Configure the input module to use the template you've defined for handling multiline messages.
3. **Define Rules to Process Multiline Logs**:
Create rules in `rsyslog` to apply your template and process the multiline log messages as required.

Here’s an example configuration to get you started:

### Define a Template

In `/etc/rsyslog.conf` or a custom configuration file under `/etc/rsyslog.d/`, define a template for handling multiline logs:

```
template(name="MultilineLog" type="string"
         string="%msg:1:999999%\\n")
```

### Configure Input Module

Specify the input module and use the defined template:

```
module(load="imfile") # Load the imfile module

input(type="imfile"
      File="/path/to/your/logfile.log"
      Tag="myapp"
      Ruleset="processMultiline")
```

### Define Ruleset to Process Multiline Logs

Create a ruleset that applies the template to process multiline messages:

```
ruleset(name="processMultiline") {
    action(type="omfile" File="/var/log/processed.log" Template="MultilineLog")
}
```

### Example Log Handling

If your log entries start with a timestamp and are followed by multiple lines, you might need a more sophisticated approach to detect and concatenate multiline entries properly. For instance, if your logs are in a format like:

```
2024-09-16 12:00:00 INFO Starting process
Additional info line 1
Additional info line 2
2024-09-16 12:01:00 INFO Process ended

```

You might need to write a script or use additional tools to preprocess and concatenate these logs before they are handled by `rsyslog`.

### Restart `rsyslog`

After updating the configuration, restart `rsyslog` to apply the changes:

```bash
sudo systemctl restart rsyslog
```

### Troubleshooting

- Ensure your log file path is correct and accessible.
- Verify that `rsyslog` is not overwriting your configuration due to syntax errors or misconfigurations.
- Check `rsyslog` logs for any errors related to the new configuration.

Feel free to adjust the example configuration to better fit your specific log format and requirements.