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Website migration is one of the most important technical projects a business can undertake, and it is also one of the easiest ways to accidentally damage years of search engine visibility.
A website may need to migrate because the business is changing domains, moving from HTTP to HTTPS, replacing an outdated CMS, redesigning its architecture, switching hosting environments, consolidating multiple websites, changing URL structures, moving from one ecommerce platform to another, or rebuilding the entire digital experience. Each of these changes can affect how search engines crawl, understand, index, and rank the website.
The central challenge is not simply moving files and databases from one server to another. A successful migration preserves the signals that have accumulated around the website over time.
Those signals can include:
When these elements are handled correctly, a website migration can be relatively smooth. When they are ignored, a technically impressive new website can launch with dramatically less organic visibility.
That is why professional website migration services treat SEO preservation as a core part of the migration process rather than something to address after launch.
Website migration is the process of moving a website from one technical, structural, hosting, domain, or platform environment to another.
The exact scope varies considerably from project to project.
A small business might move its website from one hosting provider to another without changing URLs. An ecommerce company might migrate thousands of product pages from one platform to another while redesigning its navigation. A large enterprise might consolidate several international domains into a single website and simultaneously change its CMS, information architecture, URL structure, and technology stack.
These projects have very different SEO risks.
Common types of website migration include:
A migration can involve one of these changes or several simultaneously.
For example, a company could move from:
www.example.com
to:
example.com
while also changing from an older CMS to a modern framework and restructuring URLs from:
example.com/products/item123
to:
example.com/products/item-name
That is not merely a hosting change. It is a complex SEO migration involving domain presentation, platform architecture, and URL changes.
Search engines do not treat a website as a collection of isolated files.
They develop an understanding of URLs, content, links, relationships, redirects, canonical signals, structured data, and other technical information over time.
When a migration changes those signals, search engines need to understand what happened.
Suppose an established page has accumulated backlinks for several years:
https://example.com/services/web-development
The business then launches a new website where that page becomes:
https://example.com/web-development-services
If the old URL simply disappears, search engines and users may encounter a dead page.
A properly implemented permanent redirect can communicate that the old location has been replaced by a new destination.
Without that relationship, the business risks losing some of the value associated with the original URL and creating unnecessary crawl and user experience problems.
The same principle applies to hundreds or thousands of URLs.
This is why SEO migration planning should happen before development begins.
Website migration services are professional services designed to plan, execute, validate, and monitor the movement of a website while minimizing technical problems and organic search disruption.
Depending on the project, website migration services may include:
The objective is straightforward:
Move the website while preserving as much of its existing search visibility, authority, functionality, and user experience as reasonably possible.
A website redesign and website migration are related but not identical.
A redesign primarily changes the appearance, experience, layout, or functionality of an existing website.
A migration involves moving the website from one environment, structure, domain, platform, or technical configuration to another.
However, redesign projects frequently become migrations.
For example, a company may redesign its website and simultaneously:
At that point, the project carries significant migration risk.
This distinction matters because a design team may focus on visual quality while an SEO team focuses on search continuity.
Both objectives need to be considered before launch.
A domain migration occurs when a website moves from one domain to another.
For example:
oldbrand.com
becomes:
newbrand.com
Domain migrations require careful planning because the website’s URL identity changes.
Important tasks include:
A domain migration should never be treated as simply purchasing a new domain and copying the website.
An HTTPS migration changes URLs such as:
http://example.com
to:
https://example.com
Although this type of migration can be relatively straightforward compared with a domain or platform migration, it still requires technical validation.
Potential issues include:
Every important HTTP URL should resolve appropriately to its HTTPS equivalent.
A CMS migration occurs when a website moves from one content management system to another.
Examples can include moving from:
The SEO challenge is that different platforms may handle URLs, metadata, media, taxonomies, redirects, pagination, structured data, and templates differently.
A page that was previously indexable could become blocked or incorrectly configured after migration.
Ecommerce migrations are particularly complex because stores can contain:
An ecommerce store with 50,000 URLs cannot be migrated safely using the same approach as a 30-page corporate website.
Product URL mapping, discontinued products, category changes, faceted navigation, canonicalization, pagination, and internal linking all need to be reviewed.
A hosting migration changes the server or hosting provider without necessarily changing the website’s URLs.
For example:
example.com
could remain exactly the same while the website moves from one infrastructure provider to another.
This migration may have limited SEO impact when executed correctly, but server problems can create serious consequences.
Potential issues include:
The goal should be to minimize downtime and ensure search engine crawlers can access the production environment normally.
A URL migration changes the website’s URL architecture.
For example:
example.com/service?id=123
might become:
example.com/services/web-development
Changing URLs can improve usability and information architecture, but every meaningful old URL needs an appropriate destination.
Large-scale URL changes require URL mapping rather than simply redirecting everything to the homepage.
A business might move content from:
blog.example.com
to:
example.com/blog/
This can change how the website is structured and managed.
The migration needs to account for:
International migrations can be significantly more complicated.
A company may have websites such as:
example.com
example.co.uk
example.de
example.fr
and decide to restructure them into country or language directories.
SEO considerations can include:
Incorrect international migration can result in the wrong language or regional page appearing in search results.
One of the most common migration mistakes is involving SEO after the new website has already been built.
By that point, important decisions may already be locked in.
The development team may have:
Fixing these issues after launch is more difficult than planning for them beforehand.
SEO migration planning should therefore begin during discovery.
The SEO team should understand:
These questions create the foundation for the migration strategy.
A migration checklist helps prevent important technical details from being overlooked.
A comprehensive checklist can include:
Before changing anything, create a snapshot of the existing website.
This baseline is essential because you cannot reliably measure migration performance if you do not know what the website looked like before migration.
A proper baseline should include technical, content, traffic, and search visibility information.
Use a reliable crawler to discover as many important URLs as possible.
The crawl should identify:
Do not assume the XML sitemap represents every important URL.
A sitemap is useful, but it is not always a complete representation of the site’s historical URL inventory.
Google Search Console can provide valuable information about search performance.
Depending on the available data, capture:
The purpose is not simply to record traffic.
It is to identify which URLs and search queries matter most.
A page receiving significant organic traffic deserves more migration attention than a page that has never generated meaningful search visibility.
Analytics data can identify pages that matter from a business perspective even if they do not currently rank strongly.
Look for:
A common mistake is to prioritize pages solely according to search traffic.
Some pages may have modest organic traffic but generate substantial revenue or qualified leads.
Those pages should also be protected.
A master URL inventory is one of the most valuable documents in an SEO migration project.
It should ideally combine information from multiple sources.
Potential sources include:
The objective is to discover URLs that may not appear in any single source.
For example, an old landing page might:
If the migration team only exports the current CMS URLs, that page could be lost.
Useful columns include:
| Field | Purpose |
| Current URL | Identifies the existing page |
| New URL | Identifies the migration destination |
| Status code | Shows current technical state |
| Indexability | Determines whether search engines can index it |
| Organic traffic | Indicates search value |
| Organic conversions | Shows business value |
| Backlinks | Helps identify authority |
| Referring domains | Indicates external support |
| Primary keyword | Helps preserve search intent |
| Page type | Product, service, blog, category, etc. |
| Current title | Preserves metadata |
| New title | Validates migration |
| Current canonical | Identifies canonical relationship |
| New canonical | Validates destination |
| Redirect required | Defines migration action |
| Redirect status | Tracks implementation |
| Notes | Captures special conditions |
This spreadsheet becomes the migration’s central control document.
Not every URL deserves identical migration treatment.
Prioritize URLs according to business and SEO value.
High-value URLs may include pages with:
For example, a service page that generates 30% of organic leads should receive substantially more attention than an outdated press-release page.
This does not mean low-value URLs should be ignored automatically.
It means migration resources should be allocated intelligently.
URL mapping is the foundation of a successful redirect strategy.
The basic principle is simple:
An old URL should redirect to the most relevant new URL that replaces its purpose.
Suppose the old website contains:
/services/web-development
and the new website uses:
/services/custom-web-development
If the new page genuinely replaces the old service page, the old URL can be mapped to the new page.
The objective is relevance.
One of the most damaging migration shortcuts is redirecting every old URL to the homepage.
For example:
oldsite.com/page-a → newsite.com/
oldsite.com/page-b → newsite.com/
oldsite.com/page-c → newsite.com/
This does not accurately communicate the relationship between the old and new content.
Users searching for a particular product, service, article, or resource may also land on an irrelevant homepage.
A better approach is to map URLs individually or according to carefully validated patterns.
Sometimes an old page genuinely has no equivalent.
Possible actions depend on the circumstances.
You might:
The correct decision depends on user intent, content purpose, backlinks, traffic, and business relevance.
Redirecting every deleted page somewhere arbitrary is not an SEO strategy.
Permanent redirects are a central component of many migrations.
A redirect tells a browser and crawler that a requested URL should be resolved through another URL.
For migrations involving changed URLs, permanent redirects can help search engines understand the new location of content.
Redirect implementation depends on the server and technology stack.
Common environments include:
The implementation method may differ, but the underlying migration principle remains the same: old URLs should lead users and crawlers to appropriate destinations.
A redirect chain occurs when:
URL A → URL B → URL C
Instead, where practical, establish:
URL A → URL C
Long chains can create unnecessary requests and complicate crawling.
They can also make debugging considerably more difficult.
A redirect loop occurs when URLs continually redirect back to one another.
For example:
URL A → URL B
and:
URL B → URL A
This prevents the destination from being reached normally.
Redirect testing should therefore be part of both pre-launch and post-launch validation.
SEO migration is not only about URLs.
Content matters.
If a high-performing page is migrated but its content is significantly reduced, the page may no longer satisfy the same search intent.
Content changes can include:
A redesign should not automatically assume that shorter content is better.
The correct objective is to make content useful, accurate, clear, and aligned with the page’s purpose.
For important pages, compare:
This makes content loss easier to identify before launch.
Metadata should be reviewed during migration rather than assumed to transfer automatically.
Important elements include:
Titles deserve particular attention because they help communicate page relevance to users and search engines.
If the existing site contains strong, intentionally optimized titles, replacing them with generic titles during migration can create unnecessary risk.
The new site’s templates should provide appropriate fields for maintaining or improving metadata.
Canonical tags help communicate the preferred version of a page when multiple URLs can represent similar or identical content.
During migration, canonical tags should be reviewed carefully.
A common problem is launching a new website where canonical tags still reference:
For example, a production page such as:
https://example.com/services
should not accidentally declare:
https://staging.example.com/services
as its canonical URL.
Every important production page should be checked for canonical accuracy.
Internal linking is often overlooked during migration.
A website may contain thousands of links embedded within:
If old URLs remain in internal links after migration, users may repeatedly encounter redirects.
This creates unnecessary technical overhead.
Where possible, internal links should point directly to the new canonical destinations.
Internal linking is also important for helping search engines discover and understand the new site architecture.
An XML sitemap provides search engines with information about URLs that the website considers important for discovery.
After migration, the sitemap should contain the appropriate new URLs.
Avoid leaving old URLs in the new production sitemap when those URLs now redirect elsewhere.
The new sitemap should generally reflect the current preferred URL structure.
After launch:
The robots.txt file can have a significant impact on crawler access.
One of the most dangerous migration mistakes is accidentally deploying a robots.txt configuration intended for staging.
For example, a staging environment may intentionally discourage crawling.
If that restriction reaches production, search engine crawlers may be prevented from accessing important sections of the site.
Before launch, compare:
After launch, verify the live file independently.
Do not assume the correct configuration was deployed.
Staging websites often contain restrictions designed to prevent accidental indexing.
These can include:
Those restrictions need to be reviewed before production deployment.
A migration can appear successful to the development team while remaining inaccessible to search engines because a staging restriction was carried into production.
Structured data can help search engines understand entities and page content.
Depending on the website, structured data may include:
During migration, structured data can disappear because the new templates do not include the old markup.
The migration team should therefore compare structured data before and after launch.
The goal should not be to copy every historical markup element blindly.
Instead, the new implementation should accurately describe the content that actually exists on the page.
Images are another frequently overlooked migration component.
Images may have search visibility, backlinks, accessibility value, and user experience importance.
During migration, verify:
Changing every image URL is not automatically harmful, but unnecessary changes increase migration complexity.
If image paths must change, ensure important references remain functional and appropriate redirects are considered where useful.
External links remain an important consideration in migration planning.
Suppose another website links to:
example.com/old-service
and the new website changes that page to:
example.com/services/service-name
If the old URL disappears, users following that backlink may encounter an error.
A properly mapped redirect can preserve the user journey and communicate the replacement relationship.
Backlink analysis can therefore help prioritize redirect work.
Pay particular attention to links from:
Not every backlink has the same practical value, so migration teams should prioritize meaningful links and pages.
Current website data is not always enough.
Some valuable URLs may have been removed before the migration project started.
Historical data can help identify them.
Sources may include:
This historical layer is especially important for established websites.
A page removed six months ago might still receive backlinks or appear in external references.
If the migration removes the historical redirect relationship as well, the business can lose useful continuity.
A staging environment provides an opportunity to identify migration problems before users and search engine crawlers encounter them.
The staging site should be crawled before production launch.
Review:
A staging crawl can uncover hundreds of issues while they are still relatively easy to fix.
One of the strongest migration validation techniques is comparative crawling.
Crawl the old site and the staging site, then compare the datasets.
Look for unexpected differences.
Examples include:
The question is not whether the new website is different.
It should be different.
The question is whether every important difference is intentional.
Modern websites need to work properly across mobile devices.
Migration testing should therefore include mobile rendering.
Check:
A page that works correctly on desktop but breaks on mobile can create user experience and business problems after migration.
A migration can unintentionally make a website slower.
Common causes include:
Performance should be measured before and after migration.
Important measurements can include:
Performance should be considered alongside functionality and SEO rather than treated as a separate afterthought.
The migration launch should be treated as a controlled technical event.
Avoid making major unrelated changes at the same time unless there is a compelling reason.
For example, combining all of the following simultaneously creates unnecessary complexity:
Sometimes multiple changes are unavoidable.
When they are, detailed documentation and testing become even more important.
Launch timing should consider:
Avoid launching immediately before a major sales event if the migration can reasonably be scheduled earlier.
If a serious technical issue appears, the team should have enough availability to investigate and correct it.
A migration-day checklist should be explicit.
Before deployment, confirm:
Immediately after deployment, check:
Once the new site is live, perform another crawl.
Do not wait several weeks before checking technical implementation.
A production crawl can reveal problems that staging did not expose.
Examples include:
The sooner these issues are discovered, the sooner they can be addressed.
Google Search Console should become one of the primary post-migration monitoring tools.
Watch for changes involving:
The migration team should establish a baseline before launch and compare subsequent data against it.
Short-term fluctuations do not automatically indicate permanent damage.
Search systems need time to crawl and process large numbers of changed URLs.
Organic traffic should be monitored at multiple levels.
Do not rely exclusively on total website traffic.
Review:
For example, total organic traffic might appear stable while traffic to high-value product pages declines significantly.
A deeper analysis can reveal this type of issue.
Rankings should be monitored for important keyword groups.
Create keyword segments such as:
Do not react to every individual ranking fluctuation.
Search rankings naturally move over time.
Instead, investigate patterns.
If dozens of pages in the same directory experience simultaneous declines after migration, that can indicate a technical or structural issue worth investigating.
One of the most important post-migration questions is:
Did any important URLs disappear unexpectedly?
Compare:
Any missing high-value URL should be investigated.
Not every 404 response is automatically a migration failure.
Websites accumulate obsolete URLs over time.
However, a sudden increase in 404 errors after migration can indicate missing redirects or broken internal links.
Prioritize errors associated with:
The goal is not necessarily to eliminate every historical 404.
The goal is to prevent meaningful migration-related losses.
A redirect spreadsheet should not be considered complete simply because the rules were uploaded.
Test the actual production behavior.
For important URLs, confirm:
For large websites, automated testing can make this process substantially more efficient.
Migration requirements vary according to website complexity.
A small website might have:
The migration can be relatively manageable.
However, important pages should still be mapped carefully.
A small website may depend heavily on a handful of service pages. Losing one of those pages can have a disproportionate business impact.
A medium website may contain:
These migrations require more systematic crawling and URL mapping.
Enterprise migrations can involve:
At enterprise scale, automation becomes critical.
A manually maintained spreadsheet may still be useful, but it cannot be the only control mechanism.
Ecommerce migrations require special attention because product and category URLs often drive significant organic revenue.
Important elements include:
Each important product URL should have a migration destination.
If a product remains available, its URL may map directly to the corresponding product page.
If a product is discontinued, the appropriate destination depends on the circumstances.
Possible approaches include:
A blanket redirect to the homepage generally does not provide a meaningful replacement for a specific product.
Filters can create enormous numbers of URLs.
For example, an ecommerce store may generate URLs based on:
During a platform migration, the parameter system may change.
This can create new crawlable URLs while simultaneously breaking historical ones.
The migration strategy should identify which faceted URLs are valuable, which should be canonicalized or restricted from indexing, and which should not be generated unnecessarily.
Content-heavy websites have another challenge: volume.
A large blog can contain thousands of articles.
During migration, content should be categorized into:
This classification helps prevent the common mistake of migrating everything without evaluation.
However, content pruning should not be performed casually.
A page with modest traffic can still support a broader topic through internal links or backlinks.
Decisions should therefore consider multiple data sources.
If URLs are redesigned before SEO mapping begins, the team may discover too late that hundreds of valuable pages have no destination.
This creates poor relevance and can lead to bad user experiences.
Historical URLs can continue to receive traffic and backlinks.
A staging directive accidentally deployed to production can prevent pages from appearing in search.
An incorrectly configured robots.txt file can restrict crawler access.
Large numbers of simultaneous changes make troubleshooting harder.
Reducing page content without considering search intent can alter the page’s ability to satisfy users.
Old internal links can create unnecessary redirects and broken journeys.
Canonical tags may continue pointing to old or incorrect URLs.
The new templates may remove useful structured data unintentionally.
Redirect rules can contain syntax errors, incorrect patterns, or unexpected destinations.
A migration can launch successfully while analytics tracking stops working.
A migration is not complete on launch day.
Post-launch monitoring is an essential part of the project.
A professional migration process can be divided into several stages.
The team identifies:
The existing site is audited to identify:
The migration strategy is created.
This usually includes:
The new website is developed according to the agreed requirements.
SEO requirements should be implemented within the website architecture rather than manually repaired after development.
The staging environment is tested extensively.
The new website is deployed.
Critical pages and technical signals are checked immediately.
Search performance and technical health are monitored over the following weeks.
Migration timelines vary considerably.
A simple hosting migration may require relatively little time.
A large ecommerce platform migration can require weeks or months of preparation.
Factors include:
A useful way to think about migration timelines is in phases rather than a single number.
This phase establishes what currently exists.
The team determines what will change and how existing SEO signals will be mapped.
The new environment is built.
The new environment is validated before launch.
The migration is deployed.
The team observes search, traffic, crawling, and technical behavior after deployment.
The more complex the website, the more time should be allocated to validation.
Website migration costs depend on the technical and SEO complexity of the project.
Pricing may be influenced by:
A small website migration may be relatively straightforward.
An enterprise migration involving hundreds of thousands of URLs, multiple countries, custom systems, and extensive redirect mapping can require significantly more planning and technical resources.
The lowest quoted migration price is not necessarily the most meaningful comparison.
The scope should be examined carefully.
A proposal that includes only technical file transfer is fundamentally different from a migration service that includes:
When evaluating a migration service, examine whether the scope includes the following.
The provider should understand the existing search landscape.
The current site’s technical configuration should be documented.
Old URLs should have clearly defined destinations where appropriate.
Redirects should be implemented and tested.
Important content and metadata should be protected.
The new website should be tested before launch.
Tracking should continue to work correctly.
Post-launch search visibility should be monitored.
404s, 5xx errors, redirect failures, canonical problems, and crawl issues should be reviewed.
The migration team should remain available to resolve unexpected issues.
If a business is evaluating a website migration provider, focus on evidence rather than broad marketing claims.
Useful questions include:
A provider should be able to explain the technical process clearly.
For businesses seeking a development partner that can combine website engineering with migration planning, Abbacus Technologies can be evaluated alongside other providers based on the project’s technical scope, SEO requirements, platform expertise, communication process, and documented experience.
A reliable migration can be organized around five principles.
Preserve valuable:
Map:
Test:
Monitor:
When unexpected changes appear:
A successful migration is not about making the new website look like the old website.
It is about making the transition understandable.
Search engines need to understand:
Users need similar clarity.
When someone follows an old link, they should ideally reach the resource that replaced it rather than a generic page.
That alignment between search engines and users is the foundation of a strong migration strategy.
For larger projects, a migration dashboard can make monitoring easier.
Useful dashboard categories include:
This creates a central view of migration health.
A sitewide traffic number can hide problems.
Consider a website with:
If /blog/ performs normally but /products/ loses significant visibility, the issue may be isolated to product migration logic.
Directory-level monitoring can therefore speed up diagnosis.
Other useful segments include:
If 1,000 product pages experience the same problem, manually reviewing 1,000 pages is inefficient.
Instead, determine whether the problem originates from the product template.
For example, if all migrated product pages have:
then the problem is probably template-level.
Fixing the template can correct a large number of pages simultaneously.
This is one reason technical migration expertise becomes increasingly important as websites grow.
Every significant migration should have documentation.
Important documentation can include:
Documentation reduces dependency on individual team members.
If someone leaves the project, another specialist should still be able to understand what happened.
A rollback plan should be prepared before launch.
It should define:
Not every fluctuation justifies rollback.
A rollback decision should be based on clearly defined technical or business criteria rather than panic over ordinary search volatility.
Before launch, classify risks.
Examples may include:
Examples may include:
Examples may include:
The purpose of risk assessment is not to discourage migration.
It is to allocate appropriate planning and testing resources.
Opinions can help with design decisions, but migration protection requires evidence.
Useful data sources include:
A URL should not be deleted simply because someone believes it is unimportant.
Similarly, a URL should not necessarily be preserved forever simply because it exists.
Data provides the context needed to make informed technical decisions.
Sometimes migration provides an opportunity to consolidate overlapping content.
For example, a website might have five articles covering closely related topics.
The new site may consolidate them into a stronger resource.
If consolidation is performed, the migration team should identify:
Consolidation should be deliberate.
The objective should be improved usefulness and clearer site architecture, not simply reducing the number of URLs.
Website architecture affects how users and crawlers navigate the site.
During migration, review:
If an important page moves from three clicks away to a deeply buried location, its discoverability can change.
Likewise, consolidating a confusing architecture may improve usability.
Architecture changes therefore deserve explicit SEO review.
JavaScript-heavy websites introduce additional considerations.
The migration team should verify that important content and links are available to search engine crawlers in an appropriate manner.
Test:
Do not assume that because content appears in a browser it will necessarily be handled identically by search systems.
Rendering should be tested deliberately.
Modern websites frequently depend on APIs.
Examples include:
Migration can break these integrations.
That can result in:
Because some of these failures may occur only after production deployment, integration testing should be part of migration validation.
A website migration should not accidentally destroy measurement continuity.
Check:
If tracking breaks, the business may interpret a measurement problem as a traffic problem.
This distinction is extremely important.
SEO traffic is valuable only when it supports business objectives.
During migration, protect important conversion mechanisms.
Review:
A page can retain search visibility while losing business value if its conversion path breaks.
A successful migration should be evaluated across multiple dimensions.
Technical success includes:
SEO continuity includes:
Business continuity includes:
A migration should therefore never be judged using one metric alone.
Before pressing the production deployment button, verify:
Website migration is often described as a technical transfer, but that description is incomplete.
A migration affects the relationship between the website, its users, search engines, content, infrastructure, and business operations.
The technical work may involve servers, databases, DNS, redirects, CMS configuration, APIs, templates, and code.
The SEO work involves preserving discoverability, URL relationships, content relevance, internal linking, metadata, canonical signals, and historical authority.
The business work involves protecting leads, sales, customer journeys, and measurement.
That is why a successful migration requires coordination across disciplines.
The strongest migration projects begin with an inventory of what exists, define what will change, map the old environment to the new one, test the implementation before launch, and monitor the new website after deployment.
The goal is not to prevent change.
The goal is to make change controlled, measurable, and understandable.
When every important URL has a destination, every critical technical signal has been reviewed, important content has been protected, analytics remains functional, and post-launch monitoring is active, a website migration becomes a managed transition rather than an uncontrolled SEO event.
A carefully planned migration can also provide an opportunity to improve the website’s architecture, performance, usability, technical foundation, and content organization.
The key is to make those improvements deliberately while preserving the signals that already contribute value.
For businesses preparing for a migration, the most important question is therefore not simply:
“Can we launch the new website?”
It is:
“Can we prove that the new website preserves and improves the important technical, search, content, and business relationships established by the old website?”
That question should guide the entire migration process.