diff --git a/.gitignore b/.gitignore
index 42b4424..5b14a42 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 **/.vagrant/
 **/*.retry
 *-console.log
+**/all.yaml
diff --git a/ch2-inventory/student-trungdc/02-nonFQDN.yml b/ch2-inventory/student-trungdc/02-nonFQDN.yml
new file mode 100644
index 0000000..10940d9
--- /dev/null
+++ b/ch2-inventory/student-trungdc/02-nonFQDN.yml
@@ -0,0 +1,12 @@
+all:
+  children:
+    ungrouped:
+      hosts:
+        centos21:
+          ansible_host: 192.168.100.21
+        centos22:
+          ansible_host: 192.168.100.22
+        ubuntu11:
+          ansible_host: 192.168.100.11
+        ubuntu12:
+          ansible_host: 192.168.100.12
diff --git a/ch2-inventory/student-trungdc/03-hostgroups-children.yml b/ch2-inventory/student-trungdc/03-hostgroups-children.yml
new file mode 100644
index 0000000..982052e
--- /dev/null
+++ b/ch2-inventory/student-trungdc/03-hostgroups-children.yml
@@ -0,0 +1,19 @@
+all:
+  children:
+    linux:
+      children:
+        centos:
+          hosts:
+            centos21:
+              ansible_host: 192.168.100.21
+            centos22:
+              ansible_host: 192.168.100.22
+        ubuntu:
+          hosts:
+            ubuntu11:
+              ansible_host: 192.168.100.11
+            ubuntu12:
+              ansible_host: 192.168.100.12
+    ungrouped:
+      hosts:
+        fakehost.local: {}
diff --git a/ch2-inventory/student-trungdc/04-hostvars.yml b/ch2-inventory/student-trungdc/04-hostvars.yml
new file mode 100644
index 0000000..f122bc8
--- /dev/null
+++ b/ch2-inventory/student-trungdc/04-hostvars.yml
@@ -0,0 +1,24 @@
+all:
+  children:
+    linux:
+      children:
+        centos:
+          hosts:
+            centos21:
+              ansible_host: 192.168.100.21
+              foo: bar1
+            centos22:
+              ansible_host: 192.168.100.22
+              foo: bar1
+        ubuntu:
+          hosts:
+            ubuntu11:
+              ansible_host: 192.168.100.11
+              foo: bar
+            ubuntu12:
+              ansible_host: 192.168.100.12
+              foo: bar2
+    ungrouped:
+      hosts:
+        fakehost.local:
+          foo: bar3
diff --git a/ch3-playbook/student-trungdc/07-install-apache-not-work.yaml b/ch3-playbook/student-trungdc/07-install-apache-not-work.yaml
new file mode 100644
index 0000000..b1ea56b
--- /dev/null
+++ b/ch3-playbook/student-trungdc/07-install-apache-not-work.yaml
@@ -0,0 +1,33 @@
+# Playbook for automated apache installation
+---
+- name: The demo playbook
+  hosts: all
+  gather_facts: yes
+  become: yes
+
+  tasks:
+    - name: Install Apache package Centos
+      yum:
+        name: httpd
+        state: latest 
+      when: ansible_os_family == 'RedHat'
+
+    - name: Install Apache package Ubuntu
+      apt:
+        name: apache2
+        state: latest
+      when: ansible_os_family == 'Debian'   
+
+    - name: Restart and enable on Centos
+      service:
+        name: httpd
+        state: restarted
+        enabled: yes
+      when: ansible_os_family == 'RedHat'
+
+    - name: Restart and enable on Ubuntu
+      service:
+        name: apache2
+        state: restarted
+        enabled: yes
+      when: ansible_os_family == 'Debian'
\ No newline at end of file