diff --git a/docs/courses/data-structure.md b/docs/courses/data-structure.md
index abe1c65..1266863 100644
--- a/docs/courses/data-structure.md
+++ b/docs/courses/data-structure.md
@@ -7,18 +7,22 @@ has_children: true
---
# Data Structure
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
## Introduction
- [리스트](https://github.com/boanlab/boanlab.github.io/blob/983f556286b0291107974c2d8fc5c556dc1a5e1d/docs/courses/data-structure/list.md)
diff --git a/docs/courses/data-structure/graph.md b/docs/courses/data-structure/graph.md
index a18b36e..ae8cdcd 100644
--- a/docs/courses/data-structure/graph.md
+++ b/docs/courses/data-structure/graph.md
@@ -6,18 +6,22 @@ grand_parent: Courses
---
# Graph
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
# 그래프
## 정의
diff --git a/docs/courses/data-structure/list.md b/docs/courses/data-structure/list.md
index 3ded3b3..a16d54f 100644
--- a/docs/courses/data-structure/list.md
+++ b/docs/courses/data-structure/list.md
@@ -6,18 +6,22 @@ grand_parent: Courses
---
# List
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
# 리스트
## 리스트
diff --git a/docs/courses/data-structure/queue.md b/docs/courses/data-structure/queue.md
index c9209ac..df02adf 100644
--- a/docs/courses/data-structure/queue.md
+++ b/docs/courses/data-structure/queue.md
@@ -6,18 +6,22 @@ grand_parent: Courses
---
# Queue
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
# 큐(Queue)
### 정의
diff --git a/docs/courses/data-structure/stack.md b/docs/courses/data-structure/stack.md
index 02d1845..4d640f5 100644
--- a/docs/courses/data-structure/stack.md
+++ b/docs/courses/data-structure/stack.md
@@ -6,18 +6,22 @@ grand_parent: Courses
---
# Stack
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
# 스택
### 정의
diff --git a/docs/courses/data-structure/tree.md b/docs/courses/data-structure/tree.md
index 5c232a8..1cc0a8f 100644
--- a/docs/courses/data-structure/tree.md
+++ b/docs/courses/data-structure/tree.md
@@ -6,18 +6,22 @@ grand_parent: Courses
---
# Tree
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
# 트리
### 정의
diff --git a/docs/courses/distributed-systems.md b/docs/courses/distributed-systems.md
index 7aa8feb..11249e6 100644
--- a/docs/courses/distributed-systems.md
+++ b/docs/courses/distributed-systems.md
@@ -7,18 +7,22 @@ has_children: true
---
# Distributed Systems
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
## Introduction
- [Introduction](https://github.com/boanlab/boanlab.github.io/blob/983f556286b0291107974c2d8fc5c556dc1a5e1d/docs/courses/distributed-systems/introduction.md)
diff --git a/docs/courses/distributed-systems/architecture.md b/docs/courses/distributed-systems/architecture.md
index ce54df7..d776da3 100644
--- a/docs/courses/distributed-systems/architecture.md
+++ b/docs/courses/distributed-systems/architecture.md
@@ -6,18 +6,22 @@ grand_parent: Courses
---
# Architecture
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
# Architecture
## What is Architecture?
diff --git a/docs/courses/distributed-systems/communication.md b/docs/courses/distributed-systems/communication.md
index 57a771f..21bb999 100644
--- a/docs/courses/distributed-systems/communication.md
+++ b/docs/courses/distributed-systems/communication.md
@@ -6,18 +6,22 @@ grand_parent: Courses
---
# Communication
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
# Communication
- 분산시스템의 Network Communication Model
diff --git a/docs/courses/distributed-systems/consistency.md b/docs/courses/distributed-systems/consistency.md
index 81358a1..b5591fa 100644
--- a/docs/courses/distributed-systems/consistency.md
+++ b/docs/courses/distributed-systems/consistency.md
@@ -6,18 +6,22 @@ grand_parent: Courses
---
# Consistency and Replication
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
# Consistency and Replication
- **Replication (복제)의 목적**
diff --git a/docs/courses/distributed-systems/coordination.md b/docs/courses/distributed-systems/coordination.md
index 136c6f5..1c070d2 100644
--- a/docs/courses/distributed-systems/coordination.md
+++ b/docs/courses/distributed-systems/coordination.md
@@ -6,18 +6,22 @@ grand_parent: Courses
---
# Coordination
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
# Coordination
### Time coordination
diff --git a/docs/courses/distributed-systems/fault_tolerance.md b/docs/courses/distributed-systems/fault_tolerance.md
index 64746d8..42057ec 100644
--- a/docs/courses/distributed-systems/fault_tolerance.md
+++ b/docs/courses/distributed-systems/fault_tolerance.md
@@ -6,18 +6,22 @@ grand_parent: Courses
---
# Fault Tolerance
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
# Fault Tolerance
### Dependability
diff --git a/docs/courses/distributed-systems/introduction.md b/docs/courses/distributed-systems/introduction.md
index b108be8..d64b73c 100644
--- a/docs/courses/distributed-systems/introduction.md
+++ b/docs/courses/distributed-systems/introduction.md
@@ -6,18 +6,22 @@ grand_parent: Courses
---
# Introduction
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
+
+
# Introduction
## 분산 시스템이란 무엇인가?
diff --git a/docs/courses/distributed-systems/naming.md b/docs/courses/distributed-systems/naming.md
index 32aa840..67214fb 100644
--- a/docs/courses/distributed-systems/naming.md
+++ b/docs/courses/distributed-systems/naming.md
@@ -6,20 +6,24 @@ grand_parent: Courses
---
# Naming
-
{: .no_toc }
## Table of contents
-
{: .no_toc .text-delta }
- TOC
- {:toc}
+{:toc}
---
# Naming
+
+
### Naming 이란?
- Naming (개체 네이밍)이란?
diff --git a/docs/wiki/add-new-disk-on-linux.md b/docs/wiki/add-new-disk-on-linux.md
new file mode 100644
index 0000000..54b3d5b
--- /dev/null
+++ b/docs/wiki/add-new-disk-on-linux.md
@@ -0,0 +1,72 @@
+---
+layout: default
+title: Add New disk on Linux
+parent: Wiki
+---
+
+# Add New disk on Linux
+{: .no_toc }
+
+## Table of contents
+{: .no_toc .text-delta }
+
+- TOC
+{:toc}
+
+---
+
+## Configuration
+
+- Make a new partition
+
+```
+sudo fdisk /dev/sdb (new disk device descriptor)
+```
+
+```
+Command (m for help): d (first, remove the previous partition if it exists)
+Command (m for help): n (then, create a new one)
+Command action
+
+e extended
+p primary partition
+=> p (set the new partition as a primary partition)
+
+Partition number (1-4):
+... (use default values) ...
+Command (m for help): w (write the change on the disk)
+```
+
+- Format the new partition
+
+```
+sudo mkfs.ext4 /dev/sdb1 (new partition device descriptor)
+```
+
+- Get the UUID of the new partition
+
+```
+sudo blkid
+```
+
+```
+(Write down the UUID of the new partition on your note)
+```
+
+- Edit the fstab configuration file
+
+```
+sudo vi /etc/fstab
+```
+
+```
+Add the following line
+UUID="the UUID of the new disk" [mount location] defaults 0 1
+(See fstab man page for a description of all options)
+```
+
+- Reboot
+
+```
+sudo reboot
+```
diff --git a/docs/wiki/arista-switch-openflow-setup.md b/docs/wiki/arista-switch-openflow-setup.md
new file mode 100644
index 0000000..9d18f5e
--- /dev/null
+++ b/docs/wiki/arista-switch-openflow-setup.md
@@ -0,0 +1,76 @@
+---
+layout: default
+title: Arista Switch Openflow Setup
+parent: Wiki
+---
+
+# Arista Switch Openflow Setup
+{: .no_toc }
+
+## Table of contents
+{: .no_toc .text-delta }
+
+- TOC
+{:toc}
+
+---
+
+## Test Environment
+
+```
+EOS-4.12.7.1 (Serial speed: 9600)
+```
+
+## How to configure OpenFlow
+
+- Default ID and password
+
+ ```
+ admin / [enter]
+ ```
+
+- Factory initialization
+
+ ```
+ # reload now
+ (">" to "#" : enable)
+ ```
+
+- Write changes into the startup configuration
+
+ ```
+ # write memory
+ # zerotouch cancel (if ZeroTouch is enabled)
+ ```
+
+- Set the IP address of the management port
+
+ ```
+ # configure terminal
+ (config) # interface management 1
+ (config-if) # ip address [switch IP]/24
+ (config-if) # end
+ ```
+
+- Set the OpenFlow configuration
+
+ ```
+ # config
+ (config) # openflow
+ (config-openflow) # controller tcp:[controller IP]:[controller port]
+ (config-openflow) # bind mode vlan
+ (config-openflow) # bind vlan 1
+ (config-openflow) # no shutdown
+ (config-openflow) # keepalive
+ ```
+
+- Show the OpenFlow configuration
+
+ ```
+ # show openflow
+ # show openflow flows
+ # show openflow ports
+ # show openflow profiles
+ # show openflow queues
+ # show openflow statistics
+ ```
diff --git a/docs/wiki/change-mac-address-of-network-interface.md b/docs/wiki/change-mac-address-of-network-interface.md
new file mode 100644
index 0000000..81d53e1
--- /dev/null
+++ b/docs/wiki/change-mac-address-of-network-interface.md
@@ -0,0 +1,26 @@
+---
+layout: default
+title: Change MAC address of Network Interface
+parent: Wiki
+---
+
+# Change MAC address of Network Interface
+{: .no_toc }
+
+## Table of contents
+{: .no_toc .text-delta }
+
+- TOC
+{:toc}
+
+---
+
+## Commands
+
+```
+vi /etc/udev/rules.d/75-mac-spoof.rules
+```
+
+```
+ACTION=="add", SUBSYSTEM=="net", ATTR{address}=="XX:XX:XX:XX:XX:XX", RUN+="/usr/bin/ip link set dev %k address YY:YY:YY:YY:YY:YY"
+```
diff --git a/docs/wiki/change-permissions-for-wordpress.md b/docs/wiki/change-permissions-for-wordpress.md
new file mode 100644
index 0000000..62753cf
--- /dev/null
+++ b/docs/wiki/change-permissions-for-wordpress.md
@@ -0,0 +1,27 @@
+---
+layout: default
+title: Change Permissions for Wordpress
+parent: Wiki
+---
+
+# Change Permissions for Wordpress
+{: .no_toc }
+
+## Table of contents
+{: .no_toc .text-delta }
+
+- TOC
+{:toc}
+
+---
+
+## How to change permissions for WordPress
+
+```
+sudo chown -R www-data:www-data wp-content
+```
+
+```
+sudo find . -type d -exec chmod 755 {} \;
+sudo find . -type f -exec chmod 644 {} \;
+```
diff --git a/docs/wiki/change-scaling-mode-of-cpus.md b/docs/wiki/change-scaling-mode-of-cpus.md
new file mode 100644
index 0000000..889c5be
--- /dev/null
+++ b/docs/wiki/change-scaling-mode-of-cpus.md
@@ -0,0 +1,65 @@
+---
+layout: default
+title: Change Scaling Mode of CPUs
+parent: Wiki
+---
+
+# Change Scaling Mode of CPUs
+{: .no_toc }
+
+## Table of contents
+{: .no_toc .text-delta }
+
+- TOC
+{:toc}
+
+---
+
+## Script
+
+```
+#!/bin/sh
+# Made by Hyeonseong Jo
+
+i=0
+nproc=`nproc`
+
+if [ $# -eq 0 ]
+then
+ echo "==================== HOW TO USE ===================="
+ echo "$0 [0:check status,1:performance,2:powersave]"
+ echo "===================================================="
+else
+ # check status
+ if [ $1 -eq 0 ]
+ then
+ while [ $i -lt $(nproc) ]
+ do
+ sudo echo "CPU$i:" `cat /sys/devices/system/cpu/cpu$i/cpufreq/scaling_governor`
+ i=`expr $i + 1`
+ done
+ # performance mode
+ elif [ $1 -eq 1 ]
+ then
+ while [ $i -lt $(nproc) ]
+ do
+ echo performance | sudo tee /sys/devices/system/cpu/cpu$i/cpufreq/scaling_governor > /dev/null
+ sudo echo "CPU$i:" `cat /sys/devices/system/cpu/cpu$i/cpufreq/scaling_governor`
+ i=`expr $i + 1`
+ done
+ # powersave mode
+ elif [ $1 -eq 2 ]
+ then
+ while [ $i -lt $(nproc) ]
+ do
+ echo powersave | sudo tee /sys/devices/system/cpu/cpu$i/cpufreq/scaling_governor > /dev/null
+ sudo echo "CPU$i:" `cat /sys/devices/system/cpu/cpu$i/cpufreq/scaling_governor`
+ i=`expr $i + 1`
+ done
+
+ # input error
+ else
+ echo "Input error!"
+ fi
+fi
+```
diff --git a/docs/wiki/change-timeout-of-grub.md b/docs/wiki/change-timeout-of-grub.md
new file mode 100644
index 0000000..872c291
--- /dev/null
+++ b/docs/wiki/change-timeout-of-grub.md
@@ -0,0 +1,29 @@
+---
+layout: default
+title: Change Timeout of Grub
+parent: Wiki
+---
+
+# Change Timeout of Grub
+{: .no_toc }
+
+## Table of contents
+{: .no_toc .text-delta }
+
+- TOC
+{:toc}
+
+---
+
+## Configuration
+
+```
+sudo vi /boot/grub/grub.cfg
+```
+
+```
+replace "set timeout=x" to "set timeout=y"
+
+x = the original value
+y = the value that you want to set
+```
diff --git a/docs/wiki/clock-skew-detected.md b/docs/wiki/clock-skew-detected.md
new file mode 100644
index 0000000..58b169f
--- /dev/null
+++ b/docs/wiki/clock-skew-detected.md
@@ -0,0 +1,28 @@
+---
+layout: default
+title: Clock Skew Detected
+parent: Wiki
+---
+
+# Clock Skew Detected
+{: .no_toc }
+
+## Table of contents
+{: .no_toc .text-delta }
+
+- TOC
+{:toc}
+
+---
+
+## Message
+
+```
+make: warning: Clock skew detected. Your build may be incomplete.
+```
+
+```
+make clean
+find . -exec touch {} \;
+make
+```
diff --git a/docs/wiki/configure-apache-access-log.md b/docs/wiki/configure-apache-access-log.md
new file mode 100644
index 0000000..61239ca
--- /dev/null
+++ b/docs/wiki/configure-apache-access-log.md
@@ -0,0 +1,33 @@
+---
+layout: default
+title: Configure Apache Access Log
+parent: Wiki
+---
+
+# Configure Apache Access Log
+{: .no_toc }
+
+## Table of contents
+{: .no_toc .text-delta }
+
+- TOC
+{:toc}
+
+---
+
+## Configuration
+
+```
+vi /etc/apache2/conf/httpd.conf
+```
+
+```
+# Enable the following modules
+LoadModule logio_module modules/mod_logio.so
+LoadModule log_config_module modules/mod_log_config.so
+
+# Find LogFormat and add the follwoing line
+LogFormat "\%{\%Y/%m/\%d \%T}t.\%{msec_frac}t SIP \%a DIP \%A DPORT \%p PID \%P Time \%D ResponseSize \%B Received \%I / Sent \%O Protocol \%H Method \%m URL \%U\%q Status \%>s" common
+
+# Comment other lines related to logging
+```
+
+