diff --git a/http/centos-5.11/ks.cfg b/http/centos-5.11/ks.cfg
index c1c974fdb..9b1036aaa 100644
--- a/http/centos-5.11/ks.cfg
+++ b/http/centos-5.11/ks.cfg
@@ -71,4 +71,4 @@ yum
 %post
 # sudo
 echo "vagrant        ALL=(ALL)       NOPASSWD: ALL" >> /etc/sudoers
-sed -i "s/^.*requiretty/#Defaults requiretty/" /etc/sudoers
+sed -i "s/^[^#].*requiretty/#Defaults requiretty/" /etc/sudoers
diff --git a/http/centos-6.7/ks.cfg b/http/centos-6.7/ks.cfg
index d7215076d..f6da105d7 100644
--- a/http/centos-6.7/ks.cfg
+++ b/http/centos-6.7/ks.cfg
@@ -66,4 +66,4 @@ nfs-utils
 sed -i -e 's/\(^SELINUX=\).*$/\1permissive/' /etc/selinux/config
 # sudo
 echo "%vagrant ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers.d/vagrant
-sed -i "s/^.*requiretty/#Defaults requiretty/" /etc/sudoers
+sed -i "s/^[^#].*requiretty/#Defaults requiretty/" /etc/sudoers
diff --git a/http/centos-7.1/ks.cfg b/http/centos-7.1/ks.cfg
index c5414695f..573a605da 100644
--- a/http/centos-7.1/ks.cfg
+++ b/http/centos-7.1/ks.cfg
@@ -76,5 +76,5 @@ bzip2
 %post
 # sudo
 echo "%vagrant ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers.d/vagrant
-sed -i "s/^.*requiretty/#Defaults requiretty/" /etc/sudoers
+sed -i "s/^[^#].*requiretty/#Defaults requiretty/" /etc/sudoers
 %end