+
+# varnish cache
+
+Module uses the `varnishstat` command to provide varnish cache statistics.
+
+It produces:
+
+1. **Client metrics**
+ * session accepted
+ * session dropped
+ * good client requests received
+
+2. **All history hit rate ratio**
+ * cache hits in percent
+ * cache miss in percent
+ * cache hits for pass percent
+
+3. **Curent poll hit rate ratio**
+ * cache hits in percent
+ * cache miss in percent
+ * cache hits for pass percent
+
+4. **Thread-related metrics** (only for varnish version 4+)
+ * total number of threads
+ * threads created
+ * threads creation failed
+ * threads hit max
+ * length os session queue
+ * sessions queued for thread
+
+5. **Backend health**
+ * backend conn. success
+ * backend conn. not attempted
+ * backend conn. too many
+ * backend conn. failures
+ * backend conn. reuses
+ * backend conn. recycles
+ * backend conn. retry
+ * backend requests made
+
+6. **Memory usage**
+ * memory available in megabytes
+ * memory allocated in megabytes
+
+7. **Problems summary**
+ * session dropped
+ * session accept failures
+ * session pipe overflow
+ * backend conn. not attempted
+ * fetch failed (all causes)
+ * backend conn. too many
+ * threads hit max
+ * threads destroyed
+ * length of session queue
+ * HTTP header overflows
+ * ESI parse errors
+ * ESI parse warnings
+
+8. **Uptime**
+ * varnish instance uptime in seconds
+
+### configuration
+
+No configuration is needed.
+
+---
+
+# web_log
+
+Tails the apache/nginx/lighttpd/gunicorn log files to collect real-time web-server statistics.
+
+It produces following charts:
+
+1. **Response by type** requests/s
+ * success (1xx, 2xx, 304)
+ * error (5xx)
+ * redirect (3xx except 304)
+ * bad (4xx)
+ * other (all other responses)
+
+2. **Response by code family** requests/s
+ * 1xx (informational)
+ * 2xx (successful)
+ * 3xx (redirect)
+ * 4xx (bad)
+ * 5xx (internal server errors)
+ * other (non-standart responses)
+ * unmatched (the lines in the log file that are not matched)
+
+3. **Detailed Response Codes** requests/s (number of responses for each response code family individually)
+
+4. **Bandwidth** KB/s
+ * received (bandwidth of requests)
+ * send (bandwidth of responses)
+
+5. **Timings** ms (request processing time)
+ * min (bandwidth of requests)
+ * max (bandwidth of responses)
+ * average (bandwidth of responses)
+
+6. **Request per url** requests/s (configured by user)
+
+7. **Http Methods** requests/s (requests per http method)
+
+8. **Http Versions** requests/s (requests per http version)
+
+9. **IP protocols** requests/s (requests per ip protocol version)
+
+10. **Curent Poll Unique Client IPs** unique ips/s (unique client IPs per data collection iteration)
+
+11. **All Time Unique Client IPs** unique ips/s (unique client IPs since the last restart of netdata)
+
+
+### configuration
+
+```yaml
+nginx_log:
+ name : 'nginx_log'
+ path : '/var/log/nginx/access.log'
+
+apache_log:
+ name : 'apache_log'
+ path : '/var/log/apache/other_vhosts_access.log'
+ categories:
+ cacti : 'cacti.*'
+ observium : 'observium'
+```
+
+Module has preconfigured jobs for nginx, apache and gunicorn on various distros.
+
+---