diff --git a/README.md b/README.md
index 5ee62da..53432d4 100644
--- a/README.md
+++ b/README.md
@@ -128,6 +128,10 @@ conf.probe.types=HttpAccessLog, HttpErrorLog
 conf.probe.httpaccesslog.file=/var/log/apache2/foo.bar.org-access.log*
 conf.probe.httperrorlog.file=/var/log/apache2/foo.bar.org-error.log*
 conf.probe.target=/srv/statoolinfos/well-known/statoolinfos/foo.bar.org-metrics.properties
+
+# Custom access log pattern with Java regex.
+# Default: "^(?<remoteAddress>[a-zA-F0-9\\\\:\\\\.]+) - (?<remoteUser>[^\\[]+) \\[(?<time>[^\\]]+)\\] \"(?<request>.*)\" (?<status>\\d+) (?<bodyBytesSent>\\d+) \"(?<referer>.*)\" \"(?<userAgent>[^\"]*)\".*$"
+conf.probe.httpaccesslog.pattern=
 ```
 
 ### Minetest metrics