Rancher

Rancher is a container management platform. Rancher natively supports and manages all of your Cattle, Kubernetes, Mesos, and Swarm clusters.

Container management

• App Catalog
• Orchestration: Compose, Kubernetes, Marathon, etc.
• Scheduling: Swarm, Kubernetes, Mesos, etc.
• Monitoring: cAdvisor, Sysdig, Datadog, etc.
• Access Control: LDAP, AD, GitHub, etc.
• Registry: DockerHub, Quay.io, etc.
• Engine: Docker, Rkt, etc.
• Security: Notary, Vault, etc.
• Network: VXLAN, IPSEC, HAProxy, etc.
• Storage: Ceph, Gluster, Swift, etc.
• Distributed DB: Etcd, Consul, MongoDB, etc.

Setup Rancher HA with AWS

NOTE: This section is currently incomplete. It will be updated soon.

For my Rancher HA with AWS setup, I will use the following:

Virtual Private Cloud (VPC)

• Virtual Private Cloud (VPC): rancher-vpc (w/3 subnets)
• VPC CIDR: 172.22.0.0/16
• Rancher management subnet: 172.22.1.0/24 (us-west-2a)

Rancher management server nodes (EC2 instances)

• Rancher management server nodes (EC2 instances running CentOS 7):
  • mgmt-host-1 (172.22.1.210)
  • mgmt-host-2 (172.22.1.211)
  • mgmt-host-3 (172.22.1.212)

Each of the Rancher management server nodes (referred to as "server nodes" from now on) will have Docker 1.10.3 installed and running.

Each of the server nodes will have the following security group inbound rules:

Security group inbound rules
Type	Protocol	Port	Source	Purpose
SSH	TCP	22	0.0.0.0/0	ssh
HTTP	TCP	80	0.0.0.0/0	http
HTTPS	TCP	443	0.0.0.0/0	https
TCP	TCP	81	0.0.0.0/0	proxy_to_http
TCP	TCP	444	0.0.0.0/0	proxy_to_https
TCP	TCP	6379	172.22.1.0/24	redis
TCP	TCP	2376	172.22.1.0/24	swarm
TCP	TCP	2181	0.0.0.0/0	zookeeper_client
TCP	TCP	2888	172.22.1.0/24	zookeeper_quorum
TCP	TCP	3888	172.22.1.0/24	zookeeper_leader
TCP	TCP	3306	172.22.1.0/24	mysql (RDS)
TCP	TCP	8080	0.0.0.0/0
TCP	TCP	18080	0.0.0.0/0	<optional>
UDP	UDP	500	172.22.1.0/24	access between nodes
UDP	UDP	4500	172.22.1.0/24	access between nodes

External database (RDS)

The external database (DB) will be running on an AWS Relational Database Service (RDS) and we shall call this RDS: "rancher-ext-db" and it will be listening on port 3306 on 172.22.1.26 and be in VPC "rancher-vpc". The RDS will be running MariaDB 10.0.24.

External load balancer (ELB)

The external load balancer (LB) will be running on an AWS Elastic Load Balancer (ELB) and we shall call this ELB: "rancher-ext-lb". It will be in VPC "rancher-vpc" and it will have the following listeners configured:

ELB listeners
Load Balancer Protocol	Load Balancer Port	Instance Protocol	Instance Port	Cipher	SSL Certificate
TCP	80	TCP	81	N/A	N/A
TCP	443	TCP	444	N/A	N/A
HTTP	8080	HTTP	8080	N/A	N/A

• Create ELB policies:

$ AWS_PROFILE=dev
$ LB_NAME=rancher-ext-lb
$ POLICY_NAME=rancher-ext-lb-ProxyProtocol-policy
$ aws --profile ${AWS_PROFILE} elb create-load-balancer-policy \
      --load-balancer-name ${LB_NAME} \
      --policy-name ${POLICY_NAME} \
      --policy-type-name ProxyProtocolPolicyType \
      --policy-attributes AttributeName=ProxyProtocol,AttributeValue=true
$ aws --profile ${AWS_PROFILE} elb set-load-balancer-policies-for-backend-server \
      --load-balancer-name ${LB_NAME} \
      --instance-port 81 \
      --policy-names ${POLICY_NAME}
$ aws --profile ${AWS_PROFILE} elb set-load-balancer-policies-for-backend-server \
      --load-balancer-name ${LB_NAME} \
      --instance-port 444 \
      --policy-names ${POLICY_NAME}

Rancher HA management stack

A fully functioning Rancher HA setup will have the following Docker containers running:

Rancher management stack
Service	Containers	IPs	Traffic to	Portsa	Traffic flow
6 x cattle
	rancher-ha-parent (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	zookeeper, redis		3306/tcp 0.0.0.0:18080->8080/tcp 0.0.0.0:2181->12181/tcp 0.0.0.0:2888->12888/tcp 0.0.0.0:3888->13888/tcp 0.0.0.0:6379->16379/tcp
	rancher-ha-cattle (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	zookeeper, redis
2 x go-machine-service
	management_go-machine-service_{1,2}	172.22.1.210, 172.22.1.211	cattle	3306, 8080
3 x load-balancer
	management_load-balancer_{1,2,3}	172.22.1.210, 172.22.1.211, 172.22.1.212	websocket-proxy, cattle	80, 443, 81, 444	0.0.0.0:80-81->80-81/tcp 0.0.0.0:443-444->443-444/tcp
3 x load-balancer-swarm
	management_load-blancer-swarm_{1,2,3}	172.22.1.210, 172.22.1.211, 172.22.1.212	websocket-proxy-ssl	2376	0.0.0.0:2376->2376/tcp
2 x rancher-compose-executor
	management_rancher-compose-executor_{1,2}	172.22.1.211, 172.22.1.212	cattle
3 x redis
	rancher-ha-redis	172.22.1.210, 172.22.1.211, 172.22.1.212	tunnel
36 x tunnel
	rancher-ha-tunnel-redis-1 (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	redis	6379	0.0.0.0:16379->127.0.0.1:6379/tcp
	rancher-ha-tunnel-redis-2 (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	redis	6379	127.0.0.1:6380->172.22.1.211:6379/tcp
	rancher-ha-tunnel-redis-3 (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	redis	6379	127.0.0.1:6381->172.22.1.212:6379/tcp
	rancher-ha-tunnel-zk-client-1 (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	zookeeper	2181	0.0.0.0:12181->127.0.0.1:2181/tcp
	rancher-ha-tunnel-zk-client-2 (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	zookeeper	2181	127.0.0.1:2182->172.22.1.211:2181/tcp
	rancher-ha-tunnel-zk-client-3 (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	zookeeper	2181	127.0.0.1:2183->172.22.1.212:2181/tcp
	rancher-ha-tunnel-zk-leader-1 (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	zookeeper	3888	0.0.0.0:13888->127.0.0.1:3888/tcp
	rancher-ha-tunnel-zk-leader-2 (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	zookeeper	3888	127.0.0.1:3889->172.22.1.211:3888/tcp
	rancher-ha-tunnel-zk-leader-3 (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	zookeeper	3888	127.0.0.1:3890->172.22.1.212:3888/tcp
	rancher-ha-tunnel-zk-quorum-1 (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	zookeeper	2888	0.0.0.0:12888->127.0.0.1:2888/tcp
	rancher-ha-tunnel-zk-quorum-2 (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	zookeeper	2888	127.0.0.1:2889->172.22.1.211:2888/tcp
	rancher-ha-tunnel-zk-quorum-3 (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	zookeeper	2888	127.0.0.1:2890->172.22.1.212:2888/tcp
2 x websocket-proxy
	management_websocket-proxy_{1,2}	172.22.1.210, 172.22.1.212	cattle
2 x websocket-proxy-ssl
	management_websocket-proxy-ssl_{1,2}	172.22.1.210, 172.22.1.211	cattle
3 x zookeeper
	rancher-ha-zk	172.22.1.210, 172.22.1.211, 172.22.1.212	tunnel
3 x rancher-ha (cluster-manager)
	rancher-ha (x3)	172.22.1.210, 172.22.1.211, 172.22.1.212	host	80, 18080, 3306	172.22.1.x:x->172.22.1.26:3306
3 x NetworkAgent
	NetworkAgent	172.22.1.210, 172.22.1.211, 172.22.1.212	all	500/udp, 4500/udp	0.0.0.0:500->500/udp 0.0.0.0:4500->4500/udp

^a TCP, unless otherwise specified.

Setup Rancher HA on bare-metal

This section will show you how to setup Rancher in High Availability (HA) mode on bare-metal servers. We will also setup a Kubernetes cluster managed by Rancher.

Since a given version of Rancher requires specific versions of Docker and Kubernetes, we will use the following:

• Hardware: 4 x bare-metal servers (rack-mounted)
• OS and software:
  • CentOS 7.4
  • Rancher v1.6
  • Docker 17.03.x-ce
  • Kubernetes 1.8

• Install Docker 17.03 (CE):

$ sudo yum update
$ curl https://releases.rancher.com/install-docker/17.03.sh | sudo sh
$ sudo systemctl enable docker
$ sudo usermod -aG docker $(whoami)  # logout and then log back in

• Check that Docker has been successfully installed:

$ docker --version
Docker version 17.03.2-ce, build f5ec1e2
$ docker run hello-world
...
This message shows that your installation appears to be working correctly.
... 

• Prevent Docker from being upgraded (i.e., lock it to always use Docker 17.03):

$ sudo yum -y install yum-versionlock
$ sudo yum versionlock add docker-ce
$ sudo yum versionlock add docker-ce-selinux
$ yum versionlock list
Loaded plugins: fastestmirror, versionlock
0:docker-ce-17.03.2.ce-1.el7.centos.*
0:docker-ce-selinux-17.03.2.ce-1.el7.centos.*

Note: If you ever need to remove this version lock, you can run `sudo yum versionlock delete docker-ce-*`.``

• Install and configure Network Time Protocol (NTP):

$ sudo yum install ntp
$ sudo systemctl start ntpd
$ sudo systemctl enable ntpd

• Configure NTP (note: add the closest NTP pool of servers to your bare-metal server's location) by editing /etc/ntp.conf and add/update the following lines:

$ sudo vi /etc/ntp.conf
restrict default nomodify notrap nopeer noquery kod limited
#...
server 0.north-america.pool.ntp.org iburst
server 1.north-america.pool.ntp.org iburst
server 2.north-america.pool.ntp.org iburst
server 3.north-america.pool.ntp.org iburst

• Restart NTP and check status:

$ sudo systemctl restart ntpd
$ ntpq -p   # list NTP pools stats
$ ntpdc -l  # list NTP clients

External links

• Official website