Hoping for some thoughts / guidance on the approach for this. I'm in the middle of a project to upgrade / migrate a SP2010 environment to SP2016. Due to the gaps in versions, the approach we're taking is to provision a SP2016 environment, create the required topology and then use a migration tool (most likely Sharegate) to actually migrate the content from the old environment to the new environment.
The existing usage is fairly simple (there's not much in the way of customisation) but the volume data is not trivial - it's at least a few hundred gb, currently all in a single content database. Due to this, as part of the migration it makes sense to reorganise a bit and ensure e.g., site collections have their own database.
Anyway, the question / guidance: there is a subsite of the root site collection which has a lot of content and this is one that I would like to move to its own site collection so its data can go in to separate content database. The issue though is that the URLs will need to remain the same post-migration because it's linked to from another system.
I'll try to illustrate! At the moment there is a SP2010 Server, which we'll call SP2010SERVER. There is a CNAME in DNS that points to (with AAM configured AFAIK) of e.g., SHAREPOINT. So at the moment you can browse the content in SP2010SERVER using the DNS name of SHAREPOINT. There is a subsite, which we'll call SUBSITE1, and the urls to it are e.g., http://sharepoint/subsite1. (Note: there are lots of other subsites and site collections with managed paths etc.)
We have the new SP2016 server; which let's say is called SP2016SERVER. When complete, the idea is to switch the DNS record so that SHAREPOINT now points at SP2016SERVER.
I need to move the current SUBSITE1 to its own site collection in the new environment whilst retaining the URL of http://sharepoint/subsite1. Migrating the content to the root site of a new site collection is fairly trivial I think but the question is how to retain the URL. I can't use a managed path (afaik) because if I configured e.g., 'subsite1' as a managed path, it would still need a site collection name after the path.
I've been looking at host-name(d) site collections as a possible solution. I think in this case you can moreorless specify any URL for the site collection, but I've not used them before and all the examples I've seen tend to use a sort of subdomain.domain.tld. type setup.
Would this work for my needs? And if not, are there any alternative solutions or options for this?
I imagine I could achieve the same with some sort of IIS magic / redirection etc. but was hoping to avoid this if possible.
Thanks for any thoughts / help!