Dave Walden @DBADaveKC LIVE Linux AG Buildout!

Thank You Sponsors Platinum Gold Silver Bronze Swag Venue

A few notes… We’re going to do this (mostly) LIVE! Things can (and probably will…) go wrong We’re using relatively new software Things may not (probably won’t…) work right Yes, I am using an unsupported operating system Bugs with Ubuntu, and RHEL/SuSE requires subscriptions to access the HA repos !!!USE SUPPORTED OS’s IN PRODUCTION!!!

In other words… I have done this once before, but: Things can break I rely on internet We may not finish the build Safety Not Guaranteed

The Scenario… We’re a traditional Windows shop, running SQL Server 2016 We’re asked by our new CTO to investigate this “SQL on Linux” thing – we have one hour We’ve had only basic experience with Linux, but are comfortable with tools We have not done this before, so we need help I know, lets use documentation from Microsoft.com!

What we’re going to do: Configure SQL Server on each node Configure Availability Group Install and configure clustering software Add the Availability Group as a resource to the cluster Fail over

How we’re going to do it: Prepare 3 VMs using Hyper-V ✓ Install CentOS 7 ✓ Install prerequisite software ✓ Install SQL Server 2017 Linux Configure a 3-node Availability Group Configure Linux clustering utilities Fail over using native tools (Hopefully…)

Tools we’ll use: CentOS 7 SQL Server 2017 Pacemaker (Cluster Resource Manager) Corosync (Cluster Communication, Quorum) PuTTY/MTPuTTY (Multi-Tab PuTTY) SQL Server Management Studio Web Browser Corosync provides reliable communication between nodes, manages cluster membership and determines quorum. Pacemaker is a cluster resource manager (CRM) that manages the resources that make up the cluster, such as IP addresses, mount points, file systems, DRBD devices, services such as MySQL or Apache and so on. Basically everything that can be monitored, stopped, started and moved around between nodes.

Node Configuration: CentOS 7 “Infrastructure Server” default install Node Names: SQLLinux01-03 IP Addresses: 10.254.254.11 - 13 Cluster Name: SQLLinux; IP 10.254.254.100 SQL Server 2017 Enterprise; latest CU

Enough PowerPoint Already… Let’s Do This!

STONITH Shoot The Other Node In The Head In the case of Heartbeat/Pacemaker HA clusters, there are basically three reasons for one node to STONITH the other: Nodes are alive but unable to communicate with each other (i.e. split-brain). A node is physically dead (kernel panic, HB/Pacemaker not running, no power, motherboard on fire and smoke seeping out of case, etc.) An HA resource failed to stop.

Unsupported Features (as of GA): Database engine Transactional replication   Merge replication Stretch DB Polybase Distributed query with 3rd-party connections System extended stored procedures (XP_CMDSHELL, etc.) Filetable CLR assemblies with the EXTERNAL_ACCESS or UNSAFE permission set Buffer Pool Extension SQL Server Agent Subsystems: CmdExec, PowerShell, Queue Reader, SSIS, SSAS, SSRS Alerts Log Reader Agent Change Data Capture Managed Backup High Availability Database mirroring Security Extensible Key Management AD Authentication for Linked Servers AD Authenticatin for Availibility Groups (AGs) Services SQL Server Browser SQL Server R services StreamInsight Analysis Services Reporting Services Data Quality Services Master Data Services

Questions? dwalden@fortifieddata.com