Trouble setting up DNS - questions around OctoDNS/ Mythic Namservers

Support
1

Problem Description

Hello, I moved to Mythic Beasts/ Sympl after Bytemark/ Symbiosis. I’m very spoilt by Symbiosis automatically setting up DNS – my knowledge of DNS is limited and I’d like to learn more.

So far I’ve done on Mythic/Sympl what I did on Bytemark/Symbiosis: created files such as dkim in the /srv/example.com/config folder, created /srv/example.com/public/htdocs and, at the registrar end, set the nameservers for the domain to ns1.mythic-beasts.com and ns2.mythic-beasts.com (on Bytemark I obvs set them to Bytemark NS)

I ran sudo sympl-dns-generate and the file config/dns/example.com.txt gets created and looks ‘good’

First question: That file starts with three headers with Bytemark nameservers like this:
.example.com::a.ns.bytemark.co.uk:300

  • Why are these lines Bytemark servers and how does this relate to my setting registrar’s namerserver entries to Mythic nameservers? Should they be set to Bytemark NS?

The domain is not found (eg URL in browser) and using the auditing script:
https://gitlab.mythic-beasts.com/sympl/sympl-scripts/-/blob/master/sympl-dns-audit gives lots of ‘empty’ entries such as this:

    Detecting authoritative DNS servers... ok
    Checking authoritative servers are in-sync... ok, will use '' for queries

    dig: couldn't get address for '': not found

    warn	example.com	A
    expected		[IP address of my VS]
    got

whois example.com
shows the mythic nameservers I’ve set.

On reading more around the forum, I think I need an additional step, installing and using OctoDNS, and I’ll follow these pointers: https://wiki.sympl.host/view/Using_OctoDNS_To_Update_DNS

Before I do it would be great to understand more what this does, as this step wasn’t necessary on Bytemark/ Symbiosis.

  • Does this ‘set off’ the propagation of what’s in /config/dns/example.com.txt to external nameservers?
  • There’s again some reference at the end to Bytemark - why?

Where it includes lines such as

     - config_example.com
     - config_subdomain1.example.com
     - config_subdomain2.example.com
  • Do I need to include subdomains such as ‘mx’ or are they transferred from the config/dns/example.com.txt file?

Finally:
In other forum posts I’ve read users who simply reverted to setting things ‘manually’ at the registrar side.

  • I can find a ‘AAAA’ record there and could point that to my IP, but I would also set all the mx, dkim etc records, right/

Thank you for the sympl project!

Environment

  • Sympl Version [9.0/10.0]: v11
    on a Mythic Beasts Virtual Server
2

They’re still there at the moment due to legacy reasons (it’s rather complex trying to work out the relevant nameservers), but a future update will remove them.

The domain is not found (eg URL in browser) and using the auditing script:
sympl-dns-audit · master · sympl.io / Sympl Scripts · GitLab gives lots of ‘empty’ entries such as this:

Ah, it looks like the domain isn’t enabled on the Mythic Beasts nameservers at the moment - you’ll want to visit My Account - Mythic Beasts and add it as a ‘3rd party domain’ - if it’s not set up at the moment an email to support should add it to the control panel, then you just need to click ‘Manage DNS’ and ‘Enable DNS’.

At that point you should be able to re-run the sympl-dns-audit script, and set the DNS up manually - it’s a little more fiddly, but if you’re not making a lot of changes or don’t have a lot of domains, it’s more strightforward than setting up OctoDNS.

The dns-audit script should help with that, as it checks what’s publicly visible and report if something doesn’t match!

3

The OctoDNS wasn’t necessary at Bytemark, because everything assued you were using their DNS servers.

The guide you quote is how I set my server up. Once the initial configuration is done, updates should be automatic from then on.

The reference to Bytemark at the end of the guide is simply because that’s the legacy script that Sympl calls to update the DNS. It’s modified in this case to use OctoDNS to propogate the DNS changes based on the OctoDNS configuration.

Andy

4

Thank you both!

add it to the control panel, then you just need to click ‘Manage DNS’ and ‘Enable DNS’. At that point you should be able to re-run the sympl-dns-audit script, and set the DNS up manually

I went down this route and the sympl-dns-audit script was indeed super useful. It’s ‘ok’ for all records now, the website shows up (though still needs SSL) and mail arrives.

Yey :slight_smile:

5

I attempted to transfer my business to MB hosting when Sympl was first launched; you see, I wanted to pull the plug on Bytemark. However, I only ever achieved partial dns setup success according to MX Toolbox (when hosting on MB). You may have MB hosting and email send/receive working but have you thoroughly checked your dns settings against the requirements of MX Toolbox? In the absence of any credible documentation, I reverted to installing Sympl on a Bytemark VM where the dns magic just works! Sadly, it looks as though I’ll be wedded to Bytemark forever unless someone produces a Sympl dns A – Z setup guide that’s written in plain English.

6

Thanks for reminding me of MX Toolbox, and sorry you couldn’t get it to work.
Mx Toolbox detected I was missing an SPF record. I then set this through the Mythic Beasts control panel and Mx Toolbox is happy. (I’m pretty sure sympl-dns-audit was happy about SPF yesterday when I set it using _spf to “v=spf1 +a +mx ?all” on the DNS configuration panel yesterday hmmm…)

Mx Toolbox still throws three warnings, two about SOA Serial Number and Expiration, which I’m not sure I’ll tackle, but one about
“Reverse DNS Resolution - No PTR Record found”
(for smtp)
I got as far as My Account - Mythic Beasts and for the IPv4 record of my server, set ‘Reverse DNS’ to:
example.com and mx.example.com
Trying each time whether mx Toolbox is happy – it still throws the same problem.
Maybe because it hasn’t had time to propagate yet?

*Does anyone know what this should be set to?
*For one domain, but also for multiple domains? It seems it takes only one value.

P.S. It has now propagated (set to mx.example.com) but now I get “Reverse DNS does not match SMTP Banner” - I’ll take it out again for now.

7

Did you resolve this in the end?

This thread was suggested as similar to my current issue, but sadly, yours doesn’t have the final chapter.

I’m guessing that when you said you had set the RDNS to example.com you had in fact set it to your own domain name, not literally example.com