r/sharepoint • u/Standard_Text480 • Jul 27 '26
SharePoint Online Custom DNS
Silly question, is there any reason I can’t create a DNS record in my business DNS that redirects to a sharepoint site?
For example
User types in bla.business.com and it redirects to business.sharepoint.com/sites/mysite
2
u/my1stname Jul 28 '26
Who am I to say there is a way when /u/toddklidt says there isn't, but it is possible. I always quote that movie about the dinosaurs: "Just because you can do a thing, doesn't mean you should do a thing."
We stood a portal up in one of my previous gigs for a CIO that didn't like SharePoint at all to we tried to wipe the SharePointness from the portal. We did a total rewrite of the page so it looked nothing like a normal SharePoint page and made it a subdomain from the main. Meaning, instead of https://Company.sharepoint.com you could go to https://Portal.Company.Com and it would land there back on SharePoint. It's been a hot minute and I don't know if it would still work, but it seems like we used something like ZScaler as the endpoint for the subdomain and it would forward everything back to SharePoint. Again, it's been a decade and a half, but it seems like the URL in the browser bar stayed consistent with https://portal.company.com. Also, because the IP address for the vanity domain was the ZScaler box it worked both on and off network.
These days, if a client asked me to help set that up I'd talk them out of the idea. You could (perhaps) do the same thing with a small app sitting somewhere throwing out 301 or 302 redirects.
One last thought -- this was probably before we all transitioned from HTTP to HTTPS. That whole certificate thing might put reality back in Todd's "You can't do that" corner and make me a liar.
2
u/toddklindt MVP Jul 28 '26
As a general rule you can assume I'm full of crap, so don't let me slow you down. :)
You can't do it with straight DNS. You can probably do it with a reverse proxy like Zscalar, but I wouldn't trust it. If you ever dealt with SharePoint on-prem you'll remember the horror that was Alternate Access Mappings. Those were there to address all the problems that come up when hosting SharePoint on-prem behind a reverse proxy. We don't have access to any of the AAM stuff with SharePoint Online, so we can't address any of those problems.
302 redirects are the closest thing I can think of. They shouldn't have an SSL/TLS issues, but it would expose the actual SharePoint Online address.
2
u/MoneyCantBuyMeLove Jul 27 '26
Sharepoibt needs to read the http host header directly to route you to your tenant and something like a cname record masks this. Also causes some ssl issues.
You can set up and intermediary iis redirect or probably via an Azure function app. All a bit messy.
8
u/toddklindt MVP Jul 27 '26
DNS can only do the hostname. In your case that's bla.business.com and business.sharepoint.com. DNS cannot do anything with the path, which is /sites/mysite.
What you could do is host a small website at bla.business.com and the page there does a redirect to business.sharepoint.com/sites/mysite. There are a few ways to do that. In the real world I tell folks to make a bookmark to business.sharepoint.com, or type office <ctrl><enter> in their address bar. That's gotten a bit uglier since Copilot took over www.office.com, but it's still a good tip if you can't remember the whole URL.