[DOC] fix erroneous "useallbackups" option in the doc

(cherry picked from commit af85d944ea8233c83b0bc66cb0ed2f2eddec8ced)

diff --git a/doc/configuration.txt b/doc/configuration.txt
index 263c6b241e80dffb78a5174851969516e86139de..68fffa9a34b48acd6a5e5efb9606635f794a4a28 100644 (file)
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -3697,7 +3697,7 @@ backup
   balancing when all other non-backup servers are unavailable. Requests coming
   with a persistence cookie referencing the server will always be served
   though. By default, only the first operational backup server is used, unless
-  the "useallbackup" option is set in the backend. See also the "useallbackup"
+  the "allbackups" option is set in the backend. See also the "allbackups"
   option.
 
 check