Server Fault Stack Exchange
Server Fault Stack Exchange

Questions tagged [domain-name-system]

The Domain Name System, usually referred to by the acronym DNS, is a hierarchical, distributed database where the keys are domain names. Questions involving publicly accessible domains should include the real, Fully Qualified Domain Name (FQDN)

DNS is the Domain Name System, a hierarchical, distributed database where the keys are domain names.

The primary references are:

  • RFC 1034 - Domain Names - Concepts and Facilities
  • RFC 1035 - Domain Names - Implementation and Specification

These documents collectively form STD 13. RFC 2181 is a frequently cited reference for STD 13 that addresses some of the more confusing areas of operation.

The most common record types found in the DNS are:

  • "A" records - the mapping from a domain name to an IPv4 address
  • "AAAA" records - the mapping from a domain name to an IPv6 address
  • "MX" records - the mapping from a domain name to the host name of an SMTP server
  • "NS" records - used to delegate a portion of the hierarchy to specific DNS servers
  • "PTR" records - typically used (via in-addr.arpa.) to map an IPv4 address back to a domain name
  • "CNAME" records - used to alias a domain name to its canonical version

DNS packets are conventionally transported over UDP and TCP port 53. UDP is more commonly used, but larger DNS responses and zone transfers require TCP. See RFC 5966.

This Wikipedia article provides an approachable introduction to DNS.

12242 questions
4
votes
8 answers

Install Zimbra, can't use current hosts file

I'm trying to install zimbra on a linux server. I downloaded the Ubuntu 12.04 LTS version of zimbra, unpacked and tried to run install.sh. But after I have approved the license I get this problem. ERROR: Installation can not proceeed. Please fix…
Icy Creature
  • 223
  • 2
  • 5
  • 11
4
votes
6 answers

DNS Server resolves server name but NOT fully qualified domain name

I have a new Windows Server 2003 machine I'm trying to configure as a DNS server and Domain Controller. Whenever I add an XP client to the domain I get the following event log error on boot up: "Windows cannot determine the user or computer name. …
Chris S.
  • 51
  • 1
  • 1
  • 4
4
votes
0 answers

Why shouldn't a domain controller use itself as its primary DNS server?

According to various sources, it's considered a best practice to configure a domain controller to use another DC as its primary DNS server, and itself as the secondary one. However, according to other sources, the reverse is true, or should at least…
Massimo
  • 70,200
  • 57
  • 200
  • 323
4
votes
1 answer

Turning Dell laptop network drivers on with no network cable plugged in?

I have a rather nonstandard installation - Windows Server 2008 R2 on a Dell Latitude E6520 laptop. I want the Windows DNS server to run when the laptop starts up, but it looks like the network drivers don't present the NIC as being ready until a…
Jez
  • 1,393
  • 2
  • 12
  • 24
4
votes
2 answers

Fixing my glue records

In reference to this question, I've been working with skv to fix their glue records and I'm sort of wondering what I should be seeing. They've called DNSMadeEasy and got assistance creating the glue records. Here's what I see when I query a TLD…
tcv
  • 651
  • 8
  • 21
4
votes
1 answer

Why can the primary record for a domain not be a CNAME record?

I have read on the internet that the primary record for a domain (eg example.com) should be an A record, and that bad things happen if you use a CNAME record. I work for a web company that has several clients. Each client has their business domain…
Erin Drummond
  • 225
  • 4
  • 8
4
votes
1 answer

How can I specify nameserver's port number in osx?

In resolver manual, it said: The address may optionally have a trailing dot followed by a port number. For example, 10.0.0.17.55 specifies that the nameserver at 10.0.0.17 uses port 55. But it doesn't work, in /etc/resolv.conf or files under…
Cofyc
  • 41
  • 1
  • 4
4
votes
1 answer

Anycast network - steps required to implement one?

As part of our cloud-based security service, we have a DNS server deployed in the cloud. Instead of providing different IPs to customers in different geo-locations, we want to use a unified Anycast network that can provide the myriad benefits of…
Vinay
  • 41
  • 1
4
votes
2 answers

Performance penalty when using CNAME

We are using the current CNAME record for a server, i.e. foo.example.com => CNAME => server1.example.com server1.example.com => CNAME => ec2-34-142-138-31.compute-1.amazonaws.com ec2-34-142-138-31.compute-1.amazonaws.com => A =>…
Ryan
  • 5,831
  • 24
  • 72
  • 91
4
votes
1 answer

One-Way Forest Trust Issue

I have a unique problem. We have inherited a domain that doesn't have a top level domain. The domain name is renob. I am trying to create a forest level trust between our production domain (jimbo.local) and this inherited domain (renob), but the…
Daniel Andryszak
  • 41
  • 2
4
votes
1 answer

Cloudflare, reverse DNS and php mail ending up in spam folder

I've been using Cloudflare to host my DNS, and PHPMailer to send e-mail through ZOHOs SMTP servers with great success, but have found that all my e-mails are hitting Gmail, Zoho and Hotmails spam folders. When I disabled Cloudflare's DNS hosting,…
Joseph Szymborski
  • 143
  • 1
  • 5
4
votes
1 answer

how to setup subdomains for AWS EC2 Ubuntu Instance?

I am trying to setup subdomains for my AWS EC2 ubuntu instance, but without enough knowledge I couldn't proceed anymore. I have a parked domain name example.com on a domain name service provider. My EC2 instance has Elastic IP associated, say…
Chung
  • 182
  • 1
  • 1
  • 7
4
votes
2 answers

Client DHCP on Linux seems to not be updating Windows AD DNS

I have an odd DNS issue that only sometimes presents itself. I have several Linux machines, running Ubuntu (10.10, 11.10, 12.04). Most of the time they work flawlessly. Sometimes, however, the system gets an IP address from DHCP, but fails to…
Richard Żak
  • 199
  • 1
  • 1
  • 9
4
votes
2 answers

The +a part of SPF records

I just want to clarify the +a part of an SPF record since I have an idea how this works but I am unsure. spf record for example.com v=spf1 +a -all My current understanding is that if there is a valid a record for the server it will be accepted. For…
dgibbs
  • 661
  • 2
  • 11
  • 22
4
votes
2 answers

I can connect, but cannot ping/route to remote VPN computers

Setup: L2TP VPN Server on a Windows Server 2008 machine which is behind a router, which is behind a modem/router. Modem/Router (IP: 192.168.2.1, Subnet: 255.255.255.0, DHCP serves 192.168.2.2 to router) ----|_ Router (IP: 192.168.2.2, Subnet:…
JakeTheSnake
  • 363
  • 1
  • 8
  • 19
1 2 3
…
99 100