Best Practices for Running SQL Servers on VMware:

1. Proper Resource Allocation: Allocate sufficient CPU, memory, and storage resources to the SQL Server VMs to ensure optimal performance and avoid resource contention.
2. Storage Performance: Use fast and low-latency storage systems for SQL Server VMs, and consider using vSphere features like VMware vSAN or Virtual Volumes (vVols) for better storage management.
3. vCPU Sizing: Size the vCPUs appropriately for SQL Server VMs. Avoid overcommitting CPU resources, and use multiple vCPU cores per socket for better performance.
4. Memory Reservations: Set memory reservations for critical SQL Server VMs to ensure they have guaranteed access to the required memory.
5. VMware Tools and VM Hardware Version: Keep VMware Tools up to date on SQL Server VMs and use the latest VM hardware version supported by your vSphere environment.
6. SQL Server Configuration: Configure SQL Server settings like max memory, parallelism, and tempdb appropriately to match the VM’s resources.
7. vMotion Considerations: Use vMotion carefully for SQL Server VMs to avoid performance impact during migration. Consider using CPU affinity and NUMA settings for large VMs.
8. Snapshots: Avoid using snapshots for long-term backups of SQL Server VMs, as they can lead to performance issues and disk space problems.
9. Monitoring and Performance Tuning: Use vSphere performance monitoring tools and SQL Server performance counters to identify and resolve performance bottlenecks.
10. Backup and Disaster Recovery: Implement a robust backup strategy for SQL Server databases, including both VM-level and database-level backups.
11. High Availability: Use SQL Server AlwaysOn Availability Groups or other clustering technologies for high availability and disaster recovery.
12. Security: Follow VMware security best practices and keep both the vSphere environment and SQL Server VMs patched and updated.
13. Network Configuration: Optimize network settings for SQL Server VMs, including network adapter type and network configurations.
14. Virtual Hardware Assist: Enable virtual hardware assist features like Virtualization-based security (VBS) and Virtual Machine Encryption for better security.
15. Database Maintenance: Regularly perform database maintenance tasks like index rebuilds and statistics updates to keep the SQL Server performance optimal.

PowerShell Script to Backup SQL Server Database:

To backup a SQL Server database using PowerShell, you can utilize the SqlServer module, which is part of the SQL Server Management Studio (SSMS) or the dbatools module, a popular community-driven module for database administration tasks. Below, I’ll provide examples for both approaches.

Using SqlServer Module:

Make sure you have the SqlServer module installed, which is available as part of the SQL Server Management Studio (SSMS). If you have SSMS installed, you should have the module.

# Connect to the SQL Server instance
$serverInstance = "<ServerName>"
$databaseName = "<DatabaseName>"
$backupFolder = "C:\Backups"

# Set the backup file name and path
$backupFileName = "$backupFolder\$databaseName-$(Get-Date -Format 'yyyyMMdd_HHmmss').bak"

# Perform the database backup
try {
    Invoke-Sqlcmd -ServerInstance $serverInstance -Database $databaseName -Query "BACKUP DATABASE $databaseName TO DISK='$backupFileName' WITH FORMAT, COMPRESSION"
    Write-Host "Database backup successful. Backup file: $backupFileName"
}
catch {
    Write-Host "Error occurred during database backup: $($_.Exception.Message)" -ForegroundColor Red
}

Replace <ServerName> and <DatabaseName> with your SQL Server instance name and the name of the database you want to back up. This script will create a full backup of the specified database in the provided $backupFolder location with a filename containing the database name and timestamp.

Using dbatools Module:

The dbatools module provides additional functionality and simplifies various database administration tasks. To use it, you need to install the module first.

# Install dbatools module (if not already installed)
Install-Module dbatools -Scope CurrentUser

# Import the dbatools module
Import-Module dbatools

# Connect to the SQL Server instance
$serverInstance = "<ServerName>"
$databaseName = "<DatabaseName>"
$backupFolder = "C:\Backups"

# Set the backup file name and path
$backupFileName = "$backupFolder\$databaseName-$(Get-Date -Format 'yyyyMMdd_HHmmss').bak"

# Perform the database backup
try {
    Backup-DbaDatabase -SqlInstance $serverInstance -Database $databaseName -Path $backupFileName -CopyOnly -CompressBackup
    Write-Host "Database backup successful. Backup file: $backupFileName"
}
catch {
    Write-Host "Error occurred during database backup: $($_.Exception.Message)" -ForegroundColor Red
}

This script will use the Backup-DbaDatabase cmdlet from the dbatools module to perform a full database backup with the CopyOnly and CompressBackup options. Again, replace <ServerName> and <DatabaseName> with your SQL Server instance name and the name of the database you want to back up.

Both scripts will create a full backup of the specified database with the current date and time appended to the backup file name. Make sure to adjust the $backupFolder variable to specify the desired backup location.