1. NTP
- Network Time Protocol
- 각 노드간의 시간을 동기화 시켜주기 위함
1-1. Install
# master node
$ sudo apt install ntp
$ sudo service ntp reload
$ sudo ntpq -p
# worker node
$ sudo apt install ntp
$ sudo service ntp reload
$ sudo ntpq -p
$ sudo vi /etc/ntp.conf # comment exist pools and add the master node
$ sudo systemctl restart ntp
$ sudo ntpq -p
2. Swap Memory
- 메모리 가용 증대
- kubernetes v12.2 alpha 이후부터는 swap 지원
- pre-alpha → alpha → beta → release candidate → RTM → GA
3. Docker
3-1. Install
$ sudo apt-get update
$ sudo apt-get install \\
apt-transport-https \\
ca-certificates \\
curl \\
gnupg \\
lsb-release
$ curl -fsSL <https://download.docker.com/linux/ubuntu/gpg> | sudo gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg
$ echo \\
"deb [arch=amd64 signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] <https://download.docker.com/linux/ubuntu> \\
$(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
$ sudo apt-get update
$ sudo apt-get install docker-ce docker-ce-cli containerd.io
$ sudo usermod -aG docker $USER # add a current user to the docker group
$ cat /etc/group
3-2. Connection Test
$ docker pull nginx # pull nginx image
$ docker run --name nginx -d -p 80:80 nginx # run nginx and detach with port-forwarding
References