This does not seem to be a DNS resolution/misconfiguration issue on Cloudflare's end.
https://172.64.80.1/ provides an error message (as it should) indicating it is a CloudFlare IP. If you can't see that in a web browser, then the issue is local to your network. The main causes that I gather would be: 1. There was a temporary cache propagation issue on CF's network. (Still not a DNS issue.) 2. Your IT department is using 172.0.0.0/9 or possibly even 172.0.0.0/8 where they intended to use 172.16.0.0/12 (RFC1918 IP space). This would block access to the netblock belonging to Cloudflare and you would have difficulty accessing thousands of websites. Side Note: 172.64.0.0/13 belongs to AS13335. You should always start with your IT department. If you are a Cloudflare customer, contact them directly. If you are a DeltaMath customer, then you need to contact them directly. Sincerely, Adam Vallee On Wed, Sep 22, 2021 at 4:03 PM Brown, William <[email protected]> wrote: > From: dns-operations <[email protected]> On Behalf Of > Erik Stian Tefre > Sent: Wednesday, September 22, 2021 3:38 PM > To: [email protected] > Subject: Re: [dns-operations] Oddness with Cloudfare authoritative servers > > > Possibly not a DNS issue at all, but something like this: > > > https://community.cloudflare.com/t/revil-ransomware/301435 > > > (Executive summary: One Cloudflare IP being blocked by a firewall > because of a different and misbehaving Cloudflare customer who happened to > serve malicious content from that same IP.) > > > Regards, > > Erik > > Interesting. The real issue I am experiencing is that I am getting > inconsistent responses from nominally the same authoritative server. It > just so happens that when we get 172.64.80.1 as the answer it fails. I > would prefer to get the correct answer so students can use the online > educational resource the district is paying for. > Confidentiality Notice: This electronic message and any attachments may > contain confidential or privileged information, and is intended only for > the individual or entity identified above as the addressee. If you are not > the addressee (or the employee or agent responsible to deliver it to the > addressee), or if this message has been addressed to you in error, you are > hereby notified that you may not copy, forward, disclose or use any part of > this message or any attachments. Please notify the sender immediately by > return e-mail or telephone and delete this message from your system. > > _______________________________________________ > dns-operations mailing list > [email protected] > https://lists.dns-oarc.net/mailman/listinfo/dns-operations >
_______________________________________________ dns-operations mailing list [email protected] https://lists.dns-oarc.net/mailman/listinfo/dns-operations
