SLES 12 for SAP 上課小記

SLES 12 for SAP 上課小記

Day 1:

下載上課檔案

安裝 7-zip

# zypper  install  p7zip

解壓縮檔案

# 7z  x  SLE321.7z.001

進入相關目錄

# cd  SLE321/

調整 install script 的權限

# chmod  a+x  install_lab_env.sh

執行環境檢查

# ./ install_lab_env.sh

如果不符合環境的要求, 會出現相關修改建議

例如我這邊就是要修改 /etc/libvirt/libvirtd.conf 相關設定

# vi   /etc/libvirt/libvirtd.conf

 Locate and uncomment/edit the following line to match:

unix_sock_group = libvirt

unix_sock_ro_perms = "0777"

unix_sock_rw_perms = "0770"

unix_sock_dir = "/var/run/libvirt"

auth_unix_ro = "none"

auth_unix_rw = "none"

listen_tcp = 1

 Locate and uncomment/edit the following line to match:

auth_tcp = "none"

重新開機

# reboot

進入相關目錄

# cd  SLE321/

執行環境檢查

# ./ install_lab_env.sh

新增檔案並加入下列設定

# vi  /etc/profile.d/libvirt.sh

 Add the following line to the end of the file:

export LIBVIRT_DEFAULT_URI="qemu:///system"

登出環境

# cd  SLE321/

執行環境檢查

# ./ install_lab_env.sh

將 root 加入 libvirt 群組

# usermod  -aG  libvirt  root

登出環境

# cd  SLE321/

執行環境檢查

# ./ install_lab_env.sh

完成環境安裝

Cluster Terminology

• Epoch - The version number of the cluster configuration / status
• Split Brain
• A state where the nodes in a cluster disagree about the current state of the cluster.  Must be resolved before the cluster can continue to operate
• Fencing
• Method to protect the cluster by denying access to resources or rebooting a node
• 隔離, 用來防止 Split Brain
• Active / Passive
• Active / Active

The SLE High Availability Extension

• Beginning with SLES 11, the cluster packages are no longer included in the base product
• Instead, the cluster stack is available as an add-on product, or extension
• SLES 12 integrates the delivery of the HA Extension into the software manager
• A separate subscription is required for each node that will run the HA Extension
• Up to 32 nodes
• Geo Cluster Extension to add multisite support

列出 pattern

# zypper  pt

Deployment Options

• Cluster Types
• Local Cluster
• Metro Cluster
• Geo Cluster

Main components of HAE

• High availability base components
• Corosync - 心跳, 透過 totem 實現同步
• Pacemaker - Cluster 的大腦
• Management tool
• crm shell ( CRM - Cluster Resource Manager )
• HAWK / HAWK2
• Stonith  
• 用來進行隔離(Fencing)
• Shoot The Other Node In the Head
• CIB
• Cluster Information Base
• 用來存放目前 Cluster 目前運作的狀態
• 只有主節點會更新.
• PE
• Policy Engine, 用來計算事件如何應對
• 運作在 DC 節點
• LRM
• Local Resource Manager
• 執行 CRM 發出的指令
• RA
• Resource Agent
• DLM
• Distributed Lock Manager
• Provide generic cluster wide locking facilities

• Storage components
• cLVMd
• 在 cluster 用 LVM
• DRBD
• (Distributed Replicated Block Device) 是 Linux 平台上的分散式儲存系統
• 不提供同時讀寫
• OCFS2 filesystem
• GFS filesystem
• Load balancing
• Linux IP Virtual Server ( IPVS )
• HAProxy
• Conntrackd

如何判斷主節點？

• Cluster 內其實沒有主節點或是副節點,
• 有DC 節點也許可以視為主節點, 上面的 PE

==== Break ====

Cluster Resource Manager ( CRM )

讓大家完成環境建置

==== Lunch Break ====

Lab1: Power On and Verify the Storage Server

Lab2: Install and Configure a Cluster

Section 3: Cluster Administration Tools

HAWK

Lab 3: Cluster Administrator Tools

透過 HAWK2 以 web去觀察 cluster

透過 crm 指令去觀察與控制 cluster

透過 pssh 指令去平行處理 ssh 指令

透過 csync2 指令去同步各個 node 的檔案