#cname-record

[sevennet-blog]

Answer: Querying DNS for CNAMEs for a server #fix #solution #computers

Answer: Querying DNS for CNAMEs for a server #fix #solution #computers

Querying DNS for CNAMEs for a server

Is there a way to query our internal DNS entries to discover all the CNAME entries that point to a particular server?

Edit: We’re a Windows environment, Server 2003.

Answer [by kce]: Querying DNS for CNAMEs for a server

You didn’t specify what your environment is but if you’re using Unix I think a combination of dig and grep should work. ns.example.comshould…

View On WordPress

[sevennet-blog]

Fixed: Why can't a domain's root be a CNAME? #answer #computers #solution

Fixed: Why can't a domain's root be a CNAME? #answer #computers #solution

Why can’t a domain’s root be a CNAME?

I’ve just read this question which essentially says that when I set up DNS for example.com, the root record can’t be a CNAME, it has to be an A record.

My question is, why?

I’m sure the clever people who designed DNS didn’t make arbitary restrictions for no reason, but I don’t see what we gain by requring root domains to be A records. I would love to just…

View On WordPress

[sevennet-blog]

How-to: How do i smoothly update ntpd's peer list? #answer #development #it

How-to: How do i smoothly update ntpd's peer list? #answer #development #it

How do i smoothly update ntpd’s peer list?

I have a network of solaris/linux servers that have ntpd configured to use a single internal server of stratum 2 through a DNS alias/CNAME. This is server is down for some time and the client servers’ clocks are out of sync.

Since we have another internal server of stratum 1 (PPS), the DNS CNAME has been modified to point to the new server (which is up).

View On WordPress

[sevennet-blog]

How-to: A Record VS. Cname Round N #development #it #fix

How-to: A Record VS. Cname Round N #development #it #fix

A Record VS. Cname Round N

Experienced DNS Admins please help me understand…

I run a small DNS server in a development environment that runs resolution for at most 5 domain names at any one time. My question stems from a discussion here: What’s the difference…

My question is this:

What should I use when I have a domain name and at least one subdomain pointing to that domain?

One Answer is this:

View On WordPress

[sevennet-blog]

How-to: Can you reference a CNAME record in an MX record? #computers #dev #development

How-to: Can you reference a CNAME record in an MX record? #computers #dev #development

Can you reference a CNAME record in an MX record?

We have several domains all pointing their MX records at mail.ourdomain.com, an internal mail server.

We are looking to outsource our email to a new supplier, who would like us to use mail.newsupplier.com; their mail server.

We’d rather not change all of the domain names to point to that MX record; several aren’t in our control, and it would mean…

View On WordPress

[sevennet-blog]

Resolved: www a-record vs cname-record #computers #development #it

Resolved: www a-record vs cname-record #computers #development #it

www a-record vs cname-record

I have a website that I will be hosting the DNS for (testing purposes at first and then it will have some limited traffic).

I have set up DNS so that site.tld has an A record to the actual IP, but I don’t know what to do about http://www.site.tld.

Both site.tld and http://www.site.tld will point to the same server / application so my logic tells me to add a CNAMEreco…

View On WordPress

[sevennet-blog]

Resolved: In DNS can an IN NS point to a CNAME? #it #computers #answer

Resolved: In DNS can an IN NS point to a CNAME? #it #computers #answer

In DNS can an IN NS point to a CNAME?

Is it allowed to have an NS record be a CNAME? E.g.:

subdomain.example.com. IN NS ns1.example.com. ns1.example.com. CNAME foo.example.com. foo.example.com. IN A 10.1.1.1

This doesn’t seem to work in bind though this (of course) does:

subdomain.example.com. IN NS foo.example.com. foo.example.com. IN A 10.1.1.1

Any pointers to RFCs prohibiting this setup…

View On WordPress

[sevennet-blog]

Solution: Not receiving mails from some senders due to DNS config #solution #it #programming

Solution: Not receiving mails from some senders due to DNS config #solution #it #programming

Not receiving mails from some senders due to DNS config

I have noticed a peculiar behavior of my google apps domain. Most of the mails come through as you would expect, but over a period of time I have come to the conclusion that mails from certainsenders don’t come through. After identifying one such sender, whose mails wouldn’t come through, I have asked him to try to send me an email and…

View On WordPress