SharePoint Migration Strategies: Moving to SharePoint Online

SharePoint Migration Strategies: Moving to SharePoint Online

Introduction

Migrating from SharePoint on-premises to SharePoint Online requires careful planning and execution. This guide covers migration assessment, tools and methods, wave planning, content remediation, hybrid scenarios, and best practices for successful cloud transitions.

Migration Assessment

Pre-Migration Analysis

Key Questions:

• How much content? (TB of data)
• How many sites? (site collections, subsites)
• What customizations? (farm solutions, custom code)
• What workflows? (SharePoint Designer, Nintex)
• What integrations? (third-party apps, custom APIs)
• What permissions? (AD groups, external users)

SharePoint Migration Assessment Tool (SMAT)

# Download SMAT
# https://aka.ms/smat

# Run assessment scan
.\SharePointMigrationAssessmentTool.exe

# Point to your SharePoint farm
# Generate assessment report

# Review outputs:
# - SiteCollections.csv - all site collections
# - CustomizedFiles.csv - customized pages/master pages
# - WorkflowScanSummary.csv - workflow usage
# - InfoPathScan.csv - InfoPath forms
# - Alerts.csv - configured alerts

Key Metrics from SMAT:

• Total storage used
• Number of site collections
• Customized pages count
• Workflow dependencies
• Large lists (>5000 items)
• InfoPath forms usage
• External sharing configuration

Content Inventory

# Generate site inventory
Add-PSSnapin Microsoft.SharePoint.PowerShell

$sites = Get-SPSite -Limit All

$inventory = @()
foreach ($site in $sites) {
    $webApp = $site.WebApplication.Url
    $storageGB = [math]::Round($site.Usage.Storage / 1GB, 2)
    $owner = $site.Owner.Email
    
    $inventory += [PSCustomObject]@{
        URL = $site.Url
        Title = $site.RootWeb.Title
        Owner = $owner
        StorageGB = $storageGB
        LastModified = $site.LastContentModifiedDate
        Template = $site.RootWeb.WebTemplate
    }
}

$inventory | Export-Csv "SiteInventory.csv" -NoTypeInformation

# Analyze storage by site
$inventory | Sort-Object StorageGB -Descending | Select-Object -First 20 | Format-Table

Customization Assessment

# Find farm solutions
Get-SPSolution | Select-Object Name, Deployed, LastOperationTime

# Find sandbox solutions
Get-SPSite -Limit All | ForEach-Object {
    $site = $_
    $solutions = Get-SPUserSolution -Site $site
    
    foreach ($solution in $solutions) {
        [PSCustomObject]@{
            Site = $site.Url
            Solution = $solution.Name
            Status = $solution.Status
        }
    }
} | Export-Csv "SandboxSolutions.csv" -NoTypeInformation

# Find customized master pages
Get-SPSite -Limit All | ForEach-Object {
    $web = $_.RootWeb
    if ($web.CustomMasterUrl -notlike "*/_catalogs/*") {
        [PSCustomObject]@{
            Site = $web.Url
            MasterPage = $web.CustomMasterUrl
        }
    }
}

Migration Tools

SharePoint Migration Tool (SPMT)

Features:

• Free Microsoft tool
• Migrates SharePoint on-prem, file shares, Box, Google Drive
• Supports large-scale migrations
• Incremental migration capability
• Reports and error handling

Install SPMT:

# Download from Microsoft
# https://aka.ms/spmt

# Or install via PowerShell
Install-Module -Name Microsoft.SharePoint.MigrationTool.PowerShell

Migration Using SPMT GUI

1. Launch SPMT
2. Sign in to Microsoft 365
3. Add source:
   • SharePoint Server (on-premises)
   • Enter server URL and credentials
4. Select content:
   • Entire site collection
   • Specific sites/libraries
   • Individual folders/files
5. Configure destination:
   • Target site URL
   • Preserve permissions
   • Version history options
6. Start migration
7. Monitor progress
8. Review reports

Migration Using SPMT PowerShell

# Import module
Import-Module Microsoft.SharePoint.MigrationTool.PowerShell

# Register source
$sourceUserName = "domain\admin"
$sourcePassword = ConvertTo-SecureString "password" -AsPlainText -Force
$sourceCred = New-Object System.Management.Automation.PSCredential($sourceUserName, $sourcePassword)

Register-SPMTMigration -SPOCredential $sourceCred `
                       -SourceSiteUrl "http://sharepoint2016/sites/team1" `
                       -TargetSiteUrl "https://contoso.sharepoint.com/sites/team1" `
                       -PreservePermissions `
                       -MigrateAllSiteFieldsAndContentTypes

# Start migration
Start-SPMTMigration

# Check status
Get-SPMTMigration

# Generate report
Export-SPMTReport -Path "C:\MigrationReports"

Bulk Migration Script

# CSV format: SourceUrl,TargetUrl
# Example:
# http://sp2016/sites/team1,https://contoso.sharepoint.com/sites/team1
# http://sp2016/sites/team2,https://contoso.sharepoint.com/sites/team2

$mappings = Import-Csv "SiteMappings.csv"

foreach ($mapping in $mappings) {
    Register-SPMTMigration -SPOCredential $sourceCred `
                           -SourceSiteUrl $mapping.SourceUrl `
                           -TargetSiteUrl $mapping.TargetUrl `
                           -PreservePermissions
}

Start-SPMTMigration -Parallel 5

# Wait for completion
do {
    $status = Get-SPMTMigration
    Write-Host "Migration status: $($status.Status)"
    Start-Sleep -Seconds 60
} while ($status.Status -eq "Running")

Write-Host "Migration completed!"

Third-Party Migration Tools

ShareGate:

• User-friendly interface
• Advanced permissions mapping
• Content remediation
• Pre-migration validation

AvePoint:

• Enterprise-scale migrations
• Automated scheduling
• Custom workflows
• Compliance preservation

Metalogix:

• Incremental migrations
• Content transformation
• Security migration
• Post-migration validation

Migration Waves Planning

Wave Strategy

Wave 1: Pilot (10% of sites)

• Select representative sites
• Include various templates and sizes
• Identify and resolve issues
• Gather user feedback

Wave 2: Early Adopters (20%)

• Power users and champions
• More complex sites
• Refine processes based on pilot

Wave 3: General Migration (70%)

• Bulk of organization
• Optimized processes
• Established support

Wave Planning Spreadsheet

Wave,SiteName,SourceURL,TargetURL,Owner,StorageGB,Priority,MigrationDate
1,HR Portal,http://sp/hr,https://contoso.sharepoint.com/sites/hr,hr@contoso.com,5.2,High,2025-01-15
1,IT Support,http://sp/it,https://contoso.sharepoint.com/sites/it,it@contoso.com,3.1,High,2025-01-15
2,Sales Team,http://sp/sales,https://contoso.sharepoint.com/sites/sales,sales@contoso.com,12.4,Medium,2025-02-01
2,Marketing,http://sp/marketing,https://contoso.sharepoint.com/sites/marketing,marketing@contoso.com,8.7,Medium,2025-02-01
3,Team Site 1,http://sp/team1,https://contoso.sharepoint.com/sites/team1,team1@contoso.com,2.1,Low,2025-03-01

Scheduling Script

$waves = Import-Csv "MigrationWaves.csv"

# Group by migration date
$schedule = $waves | Group-Object MigrationDate

foreach ($date in $schedule) {
    $migrationDate = [datetime]$date.Name
    
    if ((Get-Date) -ge $migrationDate) {
        Write-Host "Starting migration for $($date.Name)" -ForegroundColor Green
        
        foreach ($site in $date.Group) {
            Write-Host "  Migrating $($site.SiteName)..."
            
            Register-SPMTMigration -SourceSiteUrl $site.SourceURL `
                                   -TargetSiteUrl $site.TargetURL `
                                   -PreservePermissions
        }
        
        Start-SPMTMigration
    }
}

Content Remediation

Large Lists

Problem: Lists with >5000 items may have view threshold issues.

Solutions:

1. Create indexed columns:

# Add index to column
$list = Get-PnPList -Identity "Large List"
$field = Get-PnPField -List $list -Identity "Modified"
$field.Indexed = $true
$field.Update()
Invoke-PnPQuery

2. Break into multiple lists:
   • Archive old items
   • Use retention policies
   • Separate by year/category

Broken Permissions

# Find sites with broken inheritance
$sites = Get-PnPSubWeb -Recurse

$brokenPermissions = @()
foreach ($site in $sites) {
    Connect-PnPOnline -Url $site.Url -Interactive
    
    $web = Get-PnPWeb
    if (-not $web.HasUniqueRoleAssignments) {
        continue
    }
    
    $brokenPermissions += [PSCustomObject]@{
        SiteURL = $site.Url
        UniquePermissions = $true
    }
}

$brokenPermissions | Export-Csv "BrokenPermissions.csv" -NoTypeInformation

Custom Content Types

# Export content types for migration
$contentTypes = Get-PnPContentType

foreach ($ct in $contentTypes | Where-Object { $ct.Group -ne "_Hidden" }) {
    $template = Get-PnPSiteTemplate -Out "$($ct.Name).xml" -Handlers ContentTypes -ContentType $ct.Name
}

# Import to destination
Connect-PnPOnline -Url "https://contoso.sharepoint.com/sites/target" -Interactive
Invoke-PnPSiteTemplate -Path "CustomContentType.xml"

Workflow Migration

SharePoint Designer 2013 Workflows:

• Document existing workflows
• Recreate in Power Automate
• Test thoroughly before migration
• Run in parallel during transition

Example workflow mapping:

Old Workflow	New Power Automate Flow
Document Approval	Start and wait for approval
Send Email on New Item	When item created → Send email
Update Item on Condition	When item modified → Condition → Update item

Hybrid Scenarios

Hybrid SharePoint

Connect on-premises SharePoint with SharePoint Online:

# Configure hybrid
# Prerequisites: Azure AD Connect, SharePoint 2016/2019

# Run Hybrid Configuration Wizard
# https://www.microsoft.com/download/details.aspx?id=51885

# Configure hybrid features:
# - Hybrid search
# - Hybrid OneDrive
# - Hybrid sites features

Hybrid Search

Inbound (Cloud to On-Prem):

# Configure cloud SSA to crawl on-prem content
# Displays on-prem results in SharePoint Online search

Outbound (On-Prem to Cloud):

# Configure on-prem SSA to display cloud results
# Unified search experience from on-prem

Phased Migration with Hybrid

1. Phase 1: Set up hybrid infrastructure
2. Phase 2: Migrate OneDrive for Business
3. Phase 3: Migrate site collections in waves
4. Phase 4: Retire on-premises infrastructure

Post-Migration Tasks

Validation Checklist

# Verify site accessibility
$targetSites = Import-Csv "MigratedSites.csv"

foreach ($site in $targetSites) {
    try {
        Connect-PnPOnline -Url $site.TargetURL -Interactive
        $web = Get-PnPWeb
        
        Write-Host "✓ $($web.Title) - Accessible" -ForegroundColor Green
    }
    catch {
        Write-Host "✗ $($site.TargetURL) - Error: $($_.Exception.Message)" -ForegroundColor Red
    }
}

Permission Verification

# Compare permissions before and after
$sourcePermissions = Import-Csv "SourcePermissions.csv"
$targetSite = "https://contoso.sharepoint.com/sites/team1"

Connect-PnPOnline -Url $targetSite -Interactive

$targetGroups = Get-PnPGroup

foreach ($sourceGroup in $sourcePermissions) {
    $targetGroup = $targetGroups | Where-Object { $_.Title -eq $sourceGroup.GroupName }
    
    if ($targetGroup) {
        $members = Get-PnPGroupMember -Identity $targetGroup.Id
        Write-Host "$($sourceGroup.GroupName): $($members.Count) members"
    }
    else {
        Write-Host "Missing group: $($sourceGroup.GroupName)" -ForegroundColor Red
    }
}

Search Reindexing

# Request full crawl of migrated content
Connect-PnPOnline -Url "https://contoso.sharepoint.com/sites/team1" -Interactive

Request-PnPReIndexWeb
Request-PnPReIndexList -Identity "Documents"

User Training

Training Topics:

• Accessing SharePoint Online
• OneDrive sync client
• Mobile apps
• Modern vs. classic experience
• Sharing and permissions
• Version history

Resources:

• Video tutorials
• Quick reference guides
• Lunch and learn sessions
• Champions network

Best Practices

Before Migration

1. Clean up content - Delete obsolete sites and documents
2. Document customizations - Inventory all customizations
3. Test pilot migrations - Validate approach with small sample
4. Plan communications - Keep users informed
5. Establish support - Have help desk ready

During Migration

1. Monitor progress - Watch SPMT logs and errors
2. Incremental approach - Migrate in manageable batches
3. Off-hours scheduling - Minimize user impact
4. Parallel migrations - Use SPMT parallel capability
5. Backup source - Keep on-prem content until validated

After Migration

1. Validate content - Spot-check migrated sites
2. Test permissions - Verify access controls
3. Reindex search - Ensure content discoverable
4. Update links - Fix hardcoded URLs
5. Decommission source - Retire on-premises after validation period

Migration Timeline Example

Month 1: Assessment and Planning
- Run SMAT
- Inventory content
- Identify customizations
- Define wave strategy

Month 2: Pilot Migration
- Migrate 5-10 pilot sites
- Validate results
- Gather feedback
- Refine processes

Month 3-4: Wave 1 & 2
- Migrate 30% of sites
- Monitor and adjust
- Provide user support

Month 5-6: Wave 3 & 4
- Migrate remaining sites
- Complete validation
- Train users

Month 7: Post-Migration
- Decommission on-premises
- Final validation
- Lessons learned

Troubleshooting

Migration Errors

"Access Denied":

• Verify credentials
• Check permissions on source and target
• Ensure migration account has site collection admin

"Item Size Exceeds Maximum":

• Files >15GB cannot migrate
• Split large files or use OneDrive sync

"Too Many Requests":

• Throttled by SharePoint
• Reduce parallel migrations
• Retry with backoff

Performance Issues

# Check migration performance
Get-SPMTMigration | Select-Object -Property Status, ItemsScanned, ItemsMigrated, BytesMigrated

# Optimize settings
Set-SPMTSettings -ParallelTaskCount 10 `
                 -UseAzureADLoginForSPO $true `
                 -PreserveUserPermissions $true

Key Takeaways

• Thorough assessment prevents migration issues
• SPMT is the recommended free migration tool
• Wave approach reduces risk and user impact
• Content remediation improves migration success
• Hybrid enables phased transitions
• Validation and testing are critical
• User training ensures adoption

Next Steps

• Run SharePoint Migration Assessment Tool
• Create detailed migration plan with waves
• Pilot migration with representative sites
• Document lessons learned for full rollout

Additional Resources

• SPMT Documentation
• Migration Assessment Tool
• Hybrid SharePoint
• Migration Best Practices

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Plan carefully. Migrate confidently.