Migration Best Practices - SMX West 2019

@basgr from @peakaceag#SMX
Bastian Grimm, Peak Ace AG | @basgr
Everything you need to know to execute a successful migration
Migration Best Practices

#SMX @basgr from @peakaceag
#1 Never change a running system!

Every (big) change brings (lots of) opportunities!
But always keep in mind: the price tag for failure is immense!
Risk Reward
User acceptance “Once in a lifetime” opportunity
Project complexity Greenfield project: question everything
Resilience/freeze Best chance to really “get shit done”
Interruption Opportunity to eliminate “legacy problems”
Politics Usually more agile vs. regular, daily business
Performance Rethink RWD/dynamic serving, HTTPS, URL design, etc.

What are your goals for migration?
The right mindset is really, really important!
I want to lose as little as
possible!” – isn’t really a
good migration objective!

Thorough documentation, in-depth definitions of requirements
and ongoing testing are essential!
Be crazy about the details

…from someone who has successfully
done this type of work before.
Ask for help…

#2 A lot of preparation

What should go, what can stay? Complete vs. partial site move?
Define your migration strategy

Pre-migration: site health check & clean up
A properly optimised domain migrates easier and more efficiently. Getting your house
in order before the move minimises the risk of losing beneficial rankings.
▪ Google Search Console: manual actions, server
errors (DNS, 4xx and 5xx response codes), mark-up
validation errors (AMP, schema.org, rich cards),
robots.txt
▪ Web crawl: internal redirects as well as redirect
chains, broken URLs, and internal links
▪ Log files: broken URLs, suspicious status codes,
crawler traps
▪ Further: perform a thorough audit, it’ll save you a
lot of time with regards to the post-migration
workload

You will need an arsenal of tools!
A lot depends on personal taste, but you’ll need at least one tool each for crawling and
log file analysis as well as search intelligence – and yes, this costs money!
Google
Big Query

At a minimum: fix broken pages & broken internal links

Figure out well in advance how to gain access to all relevant server
access logs, e.g. via native access or by using a SaaS solution.
Gain access to server logs

Gather all URLs including static assets #1
Must haves: log files, XML sitemaps as well as a full website crawl.
Extras: analytics (top ranking URLs and/or URLs generating the most traffic).
small domains
large domains

Gather all URLs including static assets #2
Additionally: collect the URLs that are strongly linked, bring a lot of traffic and/or have
been shared the most, etc.

Switch to monitor your keyword rankings, daily
Check critical keywords daily to ensure you are only working with the most recent data.

Establish a status quo performance benchmark
Lighthouse (via Chrome DevTools) or webpagetest.org provide relevant metrics.
Important: also benchmark category/product pages, not just the homepage.

As a rule of thumb: 1-to-1 redirects from old to new!
Prepare for URL redirect mapping

Provide staging/test server
Make sure the server is locked-down properly to ensure your content doesn’t get
indexed in advance (i.a. duplicate content problems).
Methodology Pros Cons
noindex (meta tag/header)
▪ External tools can access without
separate access rules
▪ URLs are definitely not indexed
▪ Indexing rules cannot fully be tested
(all noindex)
▪ Waste of crawl budget
robots.txt
▪ External tools can access without
separate access rules
▪ No crawl budget is wasted
▪ Indexing rules cannot fully be tested
(only with robots.txt override)
▪ If linked, test URLs may appear in the index
(without title/metas).
password secured (.htaccess)
▪ Everything can be tested properly
▪ External tools must be able to handle
password authentication.
IP-based access
▪ Everything can be tested properly
▪ External tools must be able to handle IP-based
authentication.
VPN ▪ Absolutely safe! ▪ So safe, only a few tools can handle it!

#3 Implement necessary changes

Migration types and their potential impact on SEO
Often these types overlap – or multiple things are done simultaneously.
Inspired by @jonoalderson: http://pa.ag/2xUCMnJ
Type Example
Hosting migrations You’re changing hosting or CDN provider(s).
You’re changing, adding, or removing server locations.
You’re changing your tech stack/caching/lbs.
Software migrations You’re changing CMS (or its version/plugins, etc.).
You’re changing the language used to render the website.
You’re merging platforms; e.g. a blog which operated on a separate domain.
Domain migrations You’re changing the main domain of your website.
You’re buying/adding new domains/subdomains to your ecosystem.
You’re moving a website, or part of a website, between domains.
Template migrations You’re changing the layout/structure/navigation of important pages.
You’re adding or removing template components.
You’re changing elements in your code, like title, canonical, or hreflang tags.

Make it a granular, multi-step approach
Doing everything at once will make debugging & rolling back an almost impossible
task!
Source: http://pa.ag/2yJqT1N

Build your very own migration QA check-list
Depending on what type of changes you’re undergoing, this needs to be adapted.
Use Aleyda’s template for more inspiration: https://pa.ag/2H6bOLH
Canonical tags & other rel-alternate annotations
Remember to annotate your dedicated mobile site and to adapt
your RSS feeds
Stage: pre-migration Who? Bastian When? 30/01/19
Multilingual setup: customise hreflang target URLs
Keep in mind: various locations can be affected (e.g. head section,
server headers, xml sitemaps)
Update pel=next/prev pagination annotations
Are you using Google´s recommendation for pagination?
Update XML sitemaps
Sitemap index file also needs to be changed if you reference it in the
robots.txt
Structured data update (schema.org)
Update your schema.org mark-up references. Short annotations like
“//schema.org“ don’t validate!
Update CDN settings and resource hints
Update requests for assets to CDNs & any resource hints (preconnect,
dns-prefetch)
Update HTTP header & customise cookie settings
If applicable, customise X-Robots header tags. Use Chrome DevTools!

Update internal links
Simply relying on redirects isn’t a migration strategy.
Links to other internal URLs Links to internal video filesLinks to internal JavaScript files
JS
HTML
source code
Links to internal image files Links to internal CSS files Links to internal web fonts

Update internal links within JavaScript files
JAVASCRIPT
files
Links to other internal URLs Links to internal image files Links to internal CSS files

Update internal links within CSS files
CSS
files
Links to internal web fontsLinks to internal image files
Links to other internal URLs

Be careful with internal redirects!
Avoid redirect chains: old URLs should lead directly to the new corresponding URLs.
Source: Redirect Chain Report via DeepCrawl

Tricky: don‘t miss “invisible“ HTTP headers!
If in use: update X-Robots header tags accordingly. Use Chrome Dev. Tools to visualise!
X-Robots rel-canonical using Apaches‘ .htaccess
<Files study.pdf>
Header add Link "<https://domain.com/html-landing/>; rel="canonical""
</Files>
Other HTTP header variants (for SEO):
▪ Link: <https://www.example.com/de/>; rel="alternate"; hreflang="de"
▪ Link: <https://www.example.com/someurl>; rel="canonical"
▪ Link: <https://cdn.example.com>; rel="dns-prefetch"

Everything updated? Side-by-side comparison crawl!
Better safe than sorry: let’s test-crawl the staging server and run a comparison to make
sure all contents are available 1:1.

#4 Work your search console

Create new properties & eventually merge them into a set
For example, properties for HTTP and HTTPS with and without www = four domains.
If you use separate mobile domains, there are six properties to set up in total!

Transfer the disavow links file in time
Especially for domains with a “questionable” link profile: GSC setup and disavow file
transfer should be done approximately 48 hours before going live!

Set your preferred domain and crawl rate (if necessary)
You don’t need to set the crawl rate, but, if you have done so previously, I would
suggest transferring the original settings (for now).

Configure geo targeting for gTLDs
Synchronise settings for international targeting (i.e. for “.com” gTLDs).

URL parameter settings in GSC
Don’t forget to synchronise the URL parameter settings if you were utilising them, or if
you require them for your site’s functionality.

Make sure that fetch & render (in GSC) works properly
Perform manual checks at least for your homepage & for each of your templates (e.g.
category, product or landing page); don‘t forget to test smartphone vs. desktop as well!

Resubmit all your XML sitemaps
Keep in mind: the new GSC no longer allows you to test the file before submitting it, so
make sure you‘re validating the XML mark-up beforehand.

After all this preparation, now you "just" need
to redirect all your URLs.
301 redirect all the things!

Even if, as some say, all redirects are equal…
…all we did for this client was change the (chained) 302/307 to 301 redirects!

Note: it only works for domain migrations!
Use the GSC “site move” feature

e.g. domain.de via GSC to domain.com/de/ won‘t work!
The destination can‘t be a gTLD folder!

List crawl of old URLs & manual SERP checks
Import old URLs, e.g. to ScreamingFrog (list mode) - only 301s should appear here.
Perform additional manual check of indexed URLs, e.g. via LinkClump add-on in Chrome.
1 2 3

The most common problem with migrations gone awry?
Missing or incorrect redirects!
Seriously: check your redirects

#5 Post-migration to-dos

Focus on 4XX and 5XX status codes first, tackle these “live”!
Log file, GSC & GA error monitoring

Peak Ace log file auditing stack
Log files are stored in Google Cloud Storage, processed in Dataprep, exported to
BigQuery and visualised in Data Studio via BigQuery Connector.
8
Google Data Studio
Data
transmission
Display
dataImport
Google Dataprep
6 7
Google BigQuery
1
Log files
GSC
API v3
GA
API v4
GA
GSC
2
3
65
Google Apps Script
DeepCrawl
API
4

Re-test: no broken URLs (4/5XXer), tracking in place,
correct metadata & other tags, indexing rules, etc.
Complete crawl of the new domain

Test and apply an “if... then... logic”
Based on your previously built QA checklist, make sure to double-check everything!
you work internationally,
then test hreflang tags/sitemap annotations.
PPC ads are shown,
then update and test the landing page URLs.
Google news listings are available,
then test the Google news sitemap.
ratings (featured snippets) are available,
then test the schema.org mark-up.
IF
SSL is also used on other subdomains,
then test these as well.
IF
IF
IF
IF

AMP, structured data and rich cards error-monitoring

Google needs to recrawl ALL the relations - this takes time!
Consider hreflang to be broken

Short-term peaks are completely normal, dramatic drops are not!
Keep an eye on crawl frequency

Compare performance side-by-side
HTTPs is usually a little bit slower (handshake etc.): compare your results.
Clear goal: never slower than before (always use HTTP/2 when switching to HTTPs).
Try it out: https://www.webpagetest.org/

Adjusting/revising external links
Not every link source needs to be updated; focus on the strongest domains (e.g. via
LRT Power*Trust or Majestic Trust Flow).
Source: Majestic

Recrawling, recalculation & the inheritance of
”trust“ may take a few weeks…
First and foremost: be patient!

Especially for new domains, two weeks is not enough:
Source: http://pa.ag/2htz26D
[…] it can take two weeks
for some sites but for
larger sites, it is more like
three months, not even
close to two weeks.

#6 Some tips to make your life easier

#1 Bulk test these things: redirects & other headers
HTTP status codes (errors, redirects, etc.) at scale, for free: httpstatus.io
Check it out: https://httpstatus.io/

#2 Bulk test these things: hreflang tags
Hreflang tags (in sitemaps) at scale, for free: technicalseo.com
Check it out: https://technicalseo.com/seo-tools/hreflang/

#3 Simulate Googlebot for smartphones with JS rendering
ScreamingFrog can do that at scale, easily; pay close attention to rendered output!
Also pretty cool: Extract > Xpath > //head/link[@rel="amphtml"]/@href

#4 Don’t forget to redirect your images as well
When changing URLs/domains, make sure to implement redirect rules for images.
Read the entire post: http://pa.ag/2yJtTLz

#5 Move and retest your robots.txt file
When changing domains, make sure to transfer (the contents of) the robots.txt!

#6 HTTP 503 is your friend
Combine with “revisit-after” to throttle crawling; never use “noindex” or 4XX instead!
Source: http://pa.ag/2xRiA5T
Webmasters should return a 503 HTTP header for all
the URLs participating in the blackout […] Googlebot's
crawling rate will drop when it sees a spike in 503 […]
as Googlebot is currently configured, it will halt all
crawling of the site if the site’s robots.txt file
returns a 503 status code for robots.txt”

#7 GSC’s DNS verification can be pretty helpful
No need to worry about missing meta tags; plus you can verify before deploying a
site/frontend to a new domain – and it’s faster!
More: http://pa.ag/2yJ7xtH

#8 Fix those redirect chains, especially on legacy sites…
…as multiple requests waste valuable performance and crawl budget!

#9 Don’t miss out on some of the non-obvious redirects
It’s not only protocol-specific and www vs. non-www redirects, but so many more…
Old URL / pattern New destination Please note
domain.com/robots.txt newdomain.com/robots.txt
domain.com/sitemap.xml newdomain.com/sitemap.xml
Redirect Sitemap Index (or *.gz files) respectively.
Don’t do this if you want to monitor de-indexation
domain.com/wp-content/uploads/*.jpg newdomain.com/images/*.jpg
If you’re moving (away) from e.g. WordPress, don’t forget your
images - all of them.
domain.com/someCRAZYurl.html newdomain.com/somecrazyurl.html
Unify to a lower-case URL; more importantly make sure your rules
on origin are case insensitive
domain.com/styles/old-*.css newdomain.com/styles/new-*.css Depending on crawl volume, also redirect old CSS and JS file URLs
Keep in mind that old URLs might come with or without query parameters –
again make sure your redirect mapping handles these accordingly.

#10 Some final technical advice concerning (301) redirects
301 redirects are cached, so make sure you really know what you're doing!
Staged 302>301 redirects during a migration are more complex, but often worth it.
Once a 301 redirect has been implemented
(and seen by Googlebot), it‘ll be cached –
make sure the destination is 100% accurate
(and returning a HTTP 200)!

#SMXInsights: So, in a nutshell…
…whenever you perform a migration, make sure you:
01
Don‘t migrate
legacy!
Do a thorough health
check and clean up
first – it‘ll be super
hard to analyse errors
later on.
02
Collect all the
necessary data in
advance!
Make sure to fully
understand your URL
portfolio, crawl & GSC
data etc.
03
Get access to server
log files!
As much as I do love
the GSC, data comes
in with a delay and
you need instant
feedback on errors,
etc.
04
Check your
redirects, twice!
Make sure to review
your redirect mapping
multiple times, ideally
with another pair of
eyes.
05
Be patient and
don‘t panic!
Don‘t freak out,
seriously. Sometimes
things can just take a
bit longer for Google
to fully process (and
to pass along signals).

twitter.com/peakaceag
facebook.com/peakaceag
www.pa.ag
ALWAYS LOOKING FOR TALENT! CHECK OUT JOBS.PA.AG
WINNER
Bastian Grimm
bg@pa.ag
Slides? No problem:
https://pa.ag/smxw19
You want our log file setup (for free)?
e-mail us > hi@pa.ag

Migration Best Practices - SMX West 2019

More Related Content

What's hot (20)

Similar to Migration Best Practices - SMX West 2019 (20)

More from Bastian Grimm (13)

Recently uploaded (20)

Migration Best Practices - SMX West 2019