diff --git a/share/man/man5/resolver.5 b/share/man/man5/resolver.5
index d5c02599baf..87921582269 100644
--- a/share/man/man5/resolver.5
+++ b/share/man/man5/resolver.5
@@ -28,7 +28,7 @@
 .\"     @(#)resolver.5	8.1 (Berkeley) 6/5/93
 .\" $FreeBSD$
 .\"
-.Dd May 25, 2021
+.Dd September 20, 2021
 .Dt RESOLVER 5
 .Os
 .Sh NAME
@@ -122,15 +122,21 @@ The syntax is
 where
 .Sy option
 is one of the following:
-.Bl -tag -width no_tld_query
+.Bl -tag -width reload-period:n
 .It Sy debug
-sets
+Enable debugging information, by setting
 .Dv RES_DEBUG
-in _res.options.
+in _res.options
+.Po see
+.Xr resolver 3
+.Pc .
 .It Sy usevc
-sets
+Use TCP connections for queries instead of UDP, by setting
 .Dv RES_USEVC
-to use TCP instead of UDP for queries.
+in _res.options
+.Po see
+.Xr resolver 3
+.Pc .
 .It Sy ndots: Ns Ar n
 sets a threshold for the number of dots which must appear in a name given to
 .Fn res_query
@@ -170,15 +176,80 @@ the allowed maximum is
 .Dv RES_MAXRETRY
 (see
 .In resolv.h ) .
+.It Sy rotate
+sets
+.Dv RES_ROTATE
+in _res.options, which causes round robin selection of nameservers
+from among those listed. This has the effect of spreading the query
+among all listed servers, rather than having all clients try the
+first listed server every time.
+.It Sy no-check-names
+sets
+.Dv RES_NOCHECKNAME
+in _res.options, which disables the modern BIND checking of incoming
+host names and mail names for invalid characters such as underscore
+.Pq `_' ,
+non-ASCII, or control characters.
+.It Sy check-names
+clears
+.Dv RES_NOCHECKNAME
+in _res.options, which enables the modern BIND checking of incoming
+host names and mail names as described above.
+This is the default.
+.It Sy edns0
+sets
+.Dv RES_USE_EDNS0
+in _res.options, to enable Extension Mechanisms for DNS
+.Pq EDNS0 ,
+as specified in RFC 2671.
+This causes the resolver to attach optional pseudo resource
+records to DNS queries to inform DNS servers of our receive
+buffer size, so they can send larger replies. DNS query packets
+with EDNS0 extension are not compatible with non-EDNS0 DNS
+servers. The option must be used only when all the DNS servers in the
+.Sy nameserver
+lines are able to handle EDNS0 extension.
+.It Sy inet6
+Enable support for IPv6-only applications, by setting
+.Dv RES_USE_INET6 in _res.options
+.Po see
+.Xr resolver 3
+.Pc .
+The option is meaningful only with certain kernel
+configuration and use of this option is discouraged.
+.It Sy insecure1
+sets
+.Dv RES_INSECURE1
+in _res.options, to not require IP source address on the
+reply packet to be equal to the servers' address.
+.It Sy insecure2
+sets
+.Dv RES_INSECURE2
+in _res.options, to not check if the query selection of
+the reply packet is equal to that of the query packet.
+For testing purposes only.
 .It Sy no_tld_query
-tells the resolver not to attempt to resolve a top level domain name, that
-is, a name that contains no dots.
-Use of this option does not prevent
-the resolver from obeying the standard
+sets
+.Dv RES_NOTLDQUERY
+in _res.options. The effect is to not attempt to resolve
+an unqualified name as if it were a top level domain (TLD),
+that is, a name that contains no dots.  This option can
+cause problems if the site has ``localhost'' as a TLD
+rather than having localhost on one or more elements of the
+search list. Use of this option
+does not prevent the resolver from obeying the standard
 .Sy domain
 and
 .Sy search
 rules with the given name.
+_res.options has
+.Dv RES_DEFNAMES
+and
+.Dv RES_DNSRCH
+enabled by default, and one or both must be enabled for
+this option to have an effect.
+.It Sy no-tld-query
+another name for no_tld_query
 .It Sy reload-period: Ns Ar n
 The resolver checks the modification time of
 .Pa /etc/resolv.conf