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Issues with upstream DNS provider

status.heroku.com

101–110 of 159 posts

Re: Issues with upstream DNS provider

#101
post #92

Earlier quoted context omitted.

No historical DNS records on that site for us unfortunately, any other possible sites to check?

This one worked for me: https://dnshistory.org/

Used this site https://www.whatsmydns.net, and it worked.

Unfortunately the Heroku issue lost us a few thousand $ alongside a few customers.

Re: Issues with upstream DNS provider

#102
post #90

Earlier quoted context omitted.

We use cloudflare. If you look up the IP address for your public domain name, you will get the cloudflare IP, yes. If you lookup the IP address of the CNAME target, you will get the heroku IP.

on Cloudflare do you create A records (with found IPs) with name "www" or "mydomain.com"? also do you make that A record proxied or no? Thank you!

Use an A record and type in @. Proxied is fine.

Re: Issues with upstream DNS provider

#103

Earlier quoted context omitted.

Hi all, deleting a root CNAME record and adding a new A record on Cloudflare was too risky for us, with its potential to impact external DNS responses, so we took the following steps instead: 1. Create a new temporary subdomain in the Cloudflare DNS panel, e.g. "temp-heroku-resolve.your-domain.com", with IPs from the responses you get by querying Heroku's upstream provider directly (`dig @1.1.1.1 +trace your-app.hero…

This is essentially doing the same thing right? What is the advantage of this method? Less DNS changes? (not trying to be snarky, trying to understand)

Nah bc you're not swapping from CNAME > A records, which could have other random networking related impacts, especially if you're running a public API.

Re: Issues with upstream DNS provider

#104

Earlier quoted context omitted.

Hi all, deleting a root CNAME record and adding a new A record on Cloudflare was too risky for us, with its potential to impact external DNS responses, so we took the following steps instead: 1. Create a new temporary subdomain in the Cloudflare DNS panel, e.g. "temp-heroku-resolve.your-domain.com", with IPs from the responses you get by querying Heroku's upstream provider directly (`dig @1.1.1.1 +trace your-app.hero…

This is essentially doing the same thing right? What is the advantage of this method? Less DNS changes? (not trying to be snarky, trying to understand)

The advantage is that you can do the CNAME swap atomically in the Cloudflare interface, instead of deleting a CNAME record and adding a new A record, which would lead to a few seconds when your DNS is entirely removed. Those few seconds may not sound like a lot, but they could be cached by Cloudflare or other external DNS resolvers, trigger "clean-up" functions within Cloudflare to remove resources associated with those domains, etc.

In our case, we have substantial logic running on the edge in Cloudflare Workers, as well as lots of other Cloudflare configuration options, and I don't even want to know what it could potentially do to our zone to remove the root DNS record that everything's tied to.

Re: Issues with upstream DNS provider

#105

We just deployed a workaround that brought our site back up. 1. Find your DNS Target in heroku. It should end with .herokudns.com 2. Lookup the historical DNS record to get the IP addresses. You can find historical DNS records here: https://securitytrails.com/dns-trails 3. Replace your CNAME record in your DNS provider with A records that point to the IP addresses you just found. Your site should come back up shortly…

Anyone know how to make this work for a subdomain?

Do you have a CNAME record pointing to a herokudns.com domain? Replace it with an A record that points to the IP instead. You can find the IP by going to /dns" rel="nofollow">https://securitytrails.com/domain/

Re: Issues with upstream DNS provider

#106
post #9

Production completely inaccessible, on the plus side I might finally now get backing to migrate away from the Heroku cesspit.

Yes, i'm also done with Heroku. What alternative do you recommend?

Render.com has been great. Our test site is up, connecting back to Heroku for postgres. ( https://www.public.pink )

I just happened to try out Render last week - perfect timing.

Re: Issues with upstream DNS provider

#108
post #56

Earlier quoted context omitted.

No historical DNS records on that site for us unfortunately, any other possible sites to check?

Try this command: nslookup DOMAIN 212.230.255.1 That is a random public DNS server I found on a DNS checker site that works (as it seems to be down from all the common ones like 8.8.8.8, 1.1.1.1, etc). DOMAIN can be your actual domain or the long heroku alias.

you saved my users! thanks so much

Re: Issues with upstream DNS provider

#109

We just deployed a workaround that brought our site back up. 1. Find your DNS Target in heroku. It should end with .herokudns.com 2. Lookup the historical DNS record to get the IP addresses. You can find historical DNS records here: https://securitytrails.com/dns-trails 3. Replace your CNAME record in your DNS provider with A records that point to the IP addresses you just found. Your site should come back up shortly…

Can someone clarify what to do if your app doesn't use a custom domain, and running `heroku domains -a` just returns `my_app.herokuapp.com`, and then entering that into https://securitytrails.com/dns-trails returns no results?
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