---
title: "Log4PHP"
slug: "log4php"
description: "Track application logs and errors with Stackify's log4php appender. Install and configure with or without the Linux agent for optimal performance."
updated: 2019-11-05T21:03:38Z
published: 2019-11-05T21:03:38Z
canonical: "docs.stackify.com/log4php"
---
> ## Documentation Index
> Fetch the complete documentation index at: https://docs.stackify.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Log4PHP
Guide on setting up Stackify's **log4php** appender to track application logs and errors.
## Installation with Linux Agent
This is the suggested installation option, offering the best logging performance.
### Install **Stackify Linux Agent**
- [Standard](/docs/linux-installation)
- [Docker](/docs/retrace-docker-install)
- [Kubernetes](/docs/retrace-kubernetes-install)
### Install **stackify/log4php** module into your project:
```
composer require stackify/log4php
```
### Configure **stackify/log4php** module
Replace **Application Name** and **Environment Name** with appropriate values.
```
```
#### Optional Settings
**Server environment variables** can be added to error log message metadata. Note: This will log all system environment variables; do not enable if sensitive information such as passwords or keys are stored this way.
```
```
## Installation without Linux Agent
This option does not require a **Stackify Linux Agent** to be installed because it sends data directly to Stackify services. It collects log entries in batches, calls curl using the exec function, and sends data to the background immediately `[exec('curl ... &')]`. This will affect the performance of your application minimally, but it requires permissions to call exec inside the PHP script and it may cause silent data loss in the event of any network issues.
### Install **stackify/log4php** module into your project:
```
composer require stackify/log4php
```
### Configure **stackify/log4php** module
Replace **Stackify API Key**, **Application Name** and **Environment Name** with appropriate values.
```
```
#### Optional Settings
**Proxy:** ExecTransport supports data delivery through proxy. Specify proxy using libcurl format: `<[protocol://][user:password@]proxyhost[:port]>`:
```
```
**Curl path:** It can be useful to specify `curl` destination path for ExecTransport. This option is set to 'curl' by default.
```
```
**Server environment variables** can be added to error log message metadata.
This will log all system environment variables; do not enable if sensitive information such as passwords or keys are stored this way.
```
```