Fix grammer error

diff --git a/doc/guide/admin/install.sdf b/doc/guide/admin/install.sdf
index 8876bb0f27912e24fab8194f0f070b6b0f5198d5..107066148e46cc740aed2898c3e99369e6fca2ec 100644 (file)
--- a/doc/guide/admin/install.sdf
+++ b/doc/guide/admin/install.sdf
@@ -118,7 +118,7 @@ H3: TCP Wrappers
 
 {{slapd}}(8) supports TCP wrappers (IP level access control filters)
 if preinstalled.  Use of TCP wrappers or other IP level access
-filters (such as those provided by IP firewall) is recommended
+filters (such as those provided by a IP-level firewall) is recommended
 for servers containing non-public information.