Revert 3cd5103c1e1aaa59bd66f7f52f6ebbcd5deb12f9

diff --git a/servconf.c b/servconf.c

index 475076bf2..318546290 100644

--- a/servconf.c

+++ b/servconf.c

@@ -308,7 +308,7 @@ fill_default_server_options(ServerOptions *options)

 	if (options->max_sessions == -1)

 		options->max_sessions = DEFAULT_SESSIONS_MAX;

 	if (options->use_dns == -1)

-		options->use_dns = 0;

+		options->use_dns = 1;

 	if (options->client_alive_interval == -1)

 		options->client_alive_interval = 0;

 	if (options->client_alive_count_max == -1)

diff --git a/sshd_config b/sshd_config

index e9045bc4d..c9042ac3c 100644

--- a/sshd_config

+++ b/sshd_config

@@ -112,7 +112,7 @@ UsePrivilegeSeparation sandbox		# Default for new installations.

 #ClientAliveInterval 0

 #ClientAliveCountMax 3

 #ShowPatchLevel no

-#UseDNS no

+#UseDNS yes

 #PidFile /var/run/sshd.pid

 #MaxStartups 10:30:100

 #PermitTunnel no

diff --git a/sshd_config.5 b/sshd_config.5

index 4fd93d68e..cf57c609f 100644

--- a/sshd_config.5

+++ b/sshd_config.5

@@ -1379,10 +1379,12 @@ should look up the remote host name and check that

 should look up the remote host name, and to check that

 the resolved host name for the remote IP address maps back to the

 very same IP address.

+The default is

+.Dq yes .

 .Pp

 If this option is set to

 .Cm no

-(the default) then only addresses and not host names may be used in

+then only addresses and not host names may be used in

 .Pa ~/.ssh/authorized_keys

 .Cm from

 and