diff --git a/cgroup-tproxy.sh b/cgroup-tproxy.sh
index c11deae..20592ec 100644
--- a/cgroup-tproxy.sh
+++ b/cgroup-tproxy.sh
@@ -40,6 +40,7 @@ enable_tcp=true
 enable_udp=true
 enable_ipv4=true
 enable_ipv6=true
+enable_dns=true
 
 ## do not modify this if you don't known what you are doing
 table=100
diff --git a/readme.md b/readme.md
index 56c49fa..f5d0d0b 100644
--- a/readme.md
+++ b/readme.md
@@ -32,6 +32,9 @@ It aslo supports global transparent proxy. See [Global transparent proxy](#globa
   Why cgroup v2?  Because simple, elegant and intuitive.
 
   For now, linux default using cgroup v1 for compatibility, this project need cgroup v2, you need disable cgroup v1 and enable cgroup v2 in your system.  see [Disabling v1 cgroups](https://wiki.archlinux.org/index.php/Cgroups#Disabling_v1_cgroups).
+  
+  - `findmnt -t cgroup,cgroup2` to find out your cgroup version
+  - `systemd-cgls` to see the cgroup hierarchical tree.
 
 - TPROXY