System Requirements and Environment Verification

Before deploying Rancher, verify the host system specifications to ensure compatibility.

Operating System Check

cat /proc/version

Linux version 3.10.0-957.21.3.el7.x86_64 (mockbuild@kbuilder.bsys.centos.org) (gcc version 4.8.5 20150623 (Red Hat 4.8.5-36) (GCC) ) #1 SMP Tue Jun 18 16:35:19 UTC 2019

cat /etc/redhat-release

CentOS Linux release 7.9.2009 (Core)

Docker Engine Verification

docker version

Client:

• Version: 1.13.1
• API Version: 1.26
• Go Version: go1.10.3

Server:

• Version: 1.13.1
• API Version: 1.26 (minimum supported: 1.12)
• OS/Arch: linux/amd64

Hardware Specifications

lscpu

Specification	Value
CPU Cores	8
Architecture	64-bit
Processor	Intel(R) Xeon(R) CPU E5-2420 v2 @ 2.20GHz
NUMA Nodes	1
L1d Cache	32K
L2 Cache	256K
L3 Cache	15360K

Memory availability can be checked using:

free -m

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Rancher Container Deployment Options

Available Image Tags

Tag	Description
rancher/rancher:latest	Most recent release build
rancher/rancher:stable	Production-ready stable version

---

Option 1: Default Self-Signed Certificate

The simplest deployment method uses Rancher's built-in self-signed certificate authority.

docker run -d --privileged --name rancher-server \
    --cpus=2 \
    --memory=2g \
    --restart=unless-stopped \
    -p 80:80 \
    -p 443:443 \
    rancher/rancher:stable

Parameter Explanations

Flag	Purpose
-d	Detached mode - container runs in background
--privileged	Grants extended privileges to container
--name	Assigns a identifiable name to container
--cpus	Limits CPU allocation to specified cores
--memory	Restricts memory usage limit
--restart	Auto-restart policy configuration
-p	Port mapping (host:container)

Monitoring Container Logs

docker logs -f rancher-server

Container Removal

docker rm -f -v rancher-server

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Option 2: Custom Self-Signed Certificate

For organizations with internal certificate authorities, mount custom SSL certificates:

docker run -d --privileged --restart=unless-stopped \
    -p 80:80 \
    -p 443:443 \
    -v /opt/ssl/certificate-chain.pem:/etc/rancher/ssl/cert.pem \
    -v /opt/ssl/private-key.pem:/etc/rancher/ssl/key.pem \
    -v /opt/ssl/ca-certificate.pem:/etc/rancher/ssl/cacerts.pem \
    rancher/rancher:stable

Certificate Directory Structure

/opt/ssl/
├── certificate-chain.pem    # Full certificate chain
├── private-key.pem          # Private key file
└── ca-certificate.pem       # CA root certificate

---

Option 3: Third-Party Trusted Certificate

Deploy with certificates from commercial Certificate Authorities:

docker run -d --privileged --restart=unless-stopped \
    -p 80:80 \
    -p 443:443 \
    -v /opt/ssl/server.pem:/etc/rancher/ssl/cert.pem \
    -v /opt/ssl/server.key:/etc/rancher/ssl/key.pem \
    rancher/rancher:stable \
    --no-cacerts

Important Notes:

• The certificate chain must be complete and ordered correctly
• Incomplete certificate chains result in SSL validation failures
• Use certificate chain verification tools before deployment
• Online tools are available to repair incomplete chains

---

Option 4: Let's Encrypt Automatic Certificates

Rancher can automatically obtain certificates from Let's Encrypt:

docker run -d --privileged --restart=unless-stopped \
    -p 80:80 \
    -p 443:443 \
    rancher/rancher:stable \
    --acme-domain rancher.example.com

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Deployment Access

After container initialization completes, access the Rancher interface:

• HTTP Interface: http://server-ip
• HTTPS Interface: https://server-ip

Initial startup may require several minutes for certificate generation.

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Resource Allocation Adjustment

If the container experiences memory constraints, dynamically update resource limits:

docker stop rancher-server
docker update --memory=4g --cpus=2 rancher-server
docker start rancher-server

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Docker Compose Deployment

For infrastructure-as-code deployments, create a compose file:

mkdir -p /opt/container-apps/rancher

docker-compose.yml:

version: '3'

services:
  rancher:
    image: rancher/rancher:stable
    container_name: rancher-server
    privileged: true
    restart: unless-stopped
    ports:
      - "80:80"
      - "443:443"
    environment:
      - CATTLE_SYSTEM_CHART_DEFAULT_BRANCH=release/v2.7
    volumes:
      - rancher-data:/var/lib/rancher
    cpus: '2'
    memory: 2g

volumes:
  rancher-data:
    driver: local

Deploy using:

docker-compose up -d

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Additional Resources

• Official Rancher Docker image tags: https://hub.docker.com/r/rancher/rancher/tags
• Rancher installation documentation: https://docs.rancher.com/