Domain Name System (DNS) is a service that provides the resolution of host names to IP addresses. Use the [tag:dns] tag when you are troubleshooting DNS issues, configuring a DNS resolver or server, or are trying to understand DNS's involvement in your situation.

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How can I update my dynamic DNS under OpenWRT?

I have an OpenWrt 10.03, and I need to update my dynamic DNS account (e.g., OpenDNS or DYNDNS) when my IP changes. How can I do this from the terminal?
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How can I resolve a hostname to an IP address in a Bash script?

What's the most concise way to resolve a hostname to an IP address in a Bash script? I'm using Arch Linux.
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How do I set my DNS when resolv.conf is being overwritten?

Most of the info I see online says to edit /etc/resolv.conf, but any changes I make there just get overridden. $ cat /etc/resolv.conf # Dynamic resolv.conf(5) file for glibc resolver(3) generated by ...
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Host lookup that respects /etc/hosts

Utilities like host and dig let you see the IP address corresponding to the host name. There is also the getent utility that can be used to query /etc/hosts or other NSS databases. I am looking for ...
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How to log all my DNS queries?

How can I create logs of every DNS query that my computer makes along with the responses it gets?
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How can I Forward a subDomain to a specific port?

My apologies if this has been asked before. I haven't found an adequate solution so... yeah. When a specific domain, "example.com" is accessed, I want it to act normally. In other words, it should go ...
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How to resolve a hostname via nsswitch?

I want to test in a script whether a hostname resolves to something other than 127.0.0.1 as a pre-flight test for an install script. The tools I know (dig, nslookup) specifically query DNS. In my ...
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Preventing internal domains names being resolved with a external DNS

I have a site with a public registered domain name on Godaddy, let's say xyz.com. Unfortunately all internal systems and DNS were set with the same domain name internally. On a systems with access ...
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1answer
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Static IP address shifting to 192.168.1.251

I have a system with a static IP address of 192.168.1.150. I configured /etc/network/interfaces manually (i.e. without using NetworkManager.) It is a web server hosting three sites. I am having ...
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how to avoid NSCD for DNS

I am using NSCD service for DNS now. But sometimes I see NSCD dying itself and DNS resolving doesn't happen properly. please tell me how can we avoid NSCD for DNS . if we bypass the NSCD what is the ...
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Cannot resolve hostname

I'm using a Debian on a RaspberryPi and the problem that I'm having is that I can't connect to the Internet. Every time I try I see a message that says "cannot resolve hostname". From the terminal, I ...
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What is the point of sshd “UseDNS” option?

I know what it does, but i don't know why. What attack(s) does it prevent ? Is it relevant for all kind of authentication methods ? (hostbased, password, publickey, keyboard-interactive ...)
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/etc/resolv.conf changes during reboot

My ISP asked me to use custom nameserver settings. I have placed these in /etc/resolv.conf. Unfortunately, every time I reboot the computer, the contents of this file is changed. To connect to the ...
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How to let `named` (bind9) forward certain domains to a different nameserver?

In dnsmasq, it's possible to forward domains to different nameservers. How can I do that in named? server=/foo.com/10.0.10.1 server=/vpn.foo.com/8.8.8.8
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DNS lookups sometimes take 5 seconds

I have a VM running Debian Wheezy on which some hostname lookups take several seconds to complete, even though the resolver replies immediately. Strangely, lookups with getaddrinfo() are affected, ...
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DNS queries not using nscd for caching

I'm trying to use nscd (Nameservices Cache Daemon) to cache DNS locally so I can stop using Bind to do it. I've gotten it started and ntpd seems to attempt to use it. But everything else for hosts ...
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How to get networkmanager to configure domain specific name servers with openresolv + dnsmasq

I often connect to multiple network simultaneously. Each of these networks provide nameserver configuration via dhcp. E.g. Network 1: (eth0): domain company1.corp # nameserver 192.168.0.253 ...
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Name resolution doesn't work, but nslookup does

I am having a very strange problem with my installation of Solaris 11. DNS resolution just won't work, but strangely enough, nslookup does and connectivity is fine: root@solarisxyz:~# ping ...
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Incoming/Outgoing seperation for VPN

My situation is that I want all my outgoing connections from my Debian server to pass through a commercial VPN service I've subscribed to, but I still want to run public-accessible services on this ...
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apache won't restart after adding VirtualHost conf file, why not?

In a CentOS 7 server, I get the following error when I type sudo apachectl restart after I add an include file at the bottom of httpd.conf: Job for httpd.service failed. See 'systemctl status ...
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1answer
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Large zone file for bind9 : ad-blocking

I was successfully using a small (20,000 entries) zone file with bind9 server, but today my data provider sent an update which caused the zone file to become 300,000+ entries large (30Mb+). The ...
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OpenConnect not resolving hostnames

I'm running LMDE 17, and I've installed OpenConnect v6 and the repository version of network-manager-openconnect. Everything is peachy, except any address for the domain companyname.local doesn't ...
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1answer
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Run SSH over a SOCKS proxy?

I need VPN-like behavior locally, without using a VPN. I've created a SOCKS proxy to a given server which is reachable from the WAN, and I want all of my traffic forwarded through that proxy so I ...
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1answer
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How do I determine where DNS requests fail in the TCP stack?

I have the networking setup described here: Why is this static route not taking effect? Currently, I can ping my DNS server but all DNS requests fail: ~$ ping 130.35.249.52 PING 130.35.249.52 ...
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Method to perform DNS lookup step very quickly during wget

When I download any document from internet using wget. It shows maximum amount of time consumed in getaddrinfo(). I know getaddrinfo() used for DNS lookup. Tell me any method, so that this time is ...
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Make nslookup use specific interface

On my computer I have two network cards. Both are using different Internet Providers service. Both Internet service provider have different DNS server and their IP address are known to me. I want to ...
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1answer
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Strange issue with curl/lynx and non resolving domains

I have a weird issue on my server in that if I use curl or lynx to try and access a URL that doesn't exist (say a non registered domain, or a domain that's not in DNS), I don't get an error, it ...
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debian, problem with DNS

When I type in "google.com," firefox tells me that the server is not found. When I type in the IP address of google, it works just fine. I was playing with this computer at another place and it ...
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Command/scripts to check the Reverse DNS Lookup time

I am working on a project in which one master communicates with numbers of slaves. For that it has to make connection with hosts in network. But sometimes it hangs. I think that the reason behind is ...
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Should /etc/hosts contain the domain name or the FQDN?

If I want to add an entry to /etc/hosts to resolve all traffic for example.com to 1.2.3.4, do I need to add 1.2.3.4 example.com 1.2.3.4 www.example.com 1.2.3.4 smtp.example.com 1.2.3.4 ...
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Blocking Websites with /etc/hosts

There's a website, www.example.com, that I tried to block myself from accessing because it wastes too much of my time. So I configured my /etc/hosts file. I added the following lines, to block the ...
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Can I set my Debian box to use OpenDNS nameservers if it uses DHCP?

I have a Debian box with this in /etc/network/interfaces: auto eth0 allow-hotplug eth0 iface eth0 inet dhcp auto wlan0 iface wlan0 inet dhcp wpa-ssid NetworkName wpa-psk NetworkPass and ...
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DNS resolution problem with OpenBSD

During boot up, messages flashed on my computer screen, among which are the following: DHCPACK from 192.168.200.1 bound to 192.168.200.12----> renewal in 432600 seconds The contents of my ...
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/usr/bin/host not picking up changes to /etc/hosts even after reboot

I have a Ubuntu Server 12.04 (amd64) machine on which, when I change /etc/hosts, the changes aren't picked up, even after a reboot. I am using /usr/bin/host to test, but none of the other programs ...
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1answer
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Ubuntu server cannot access the Internet: appears DNS related

This is a Drupal website running Ubuntu 12.04 LTS on Linode. The server is just a website. It is not a DNS server or anything else. Here are my issues. It seems they are all related to DNS issues. ...
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Different domains for multiple VM's on host with one WAN IP

I've got only one WAN IP address bound to KVM host system and multiple VM's with internal IP's, say, 10.0.0.1/28. On the other hand I have multiple domain names bound to host system WAN IP. The ...
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2answers
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Virtual hosting a tomcat webapp in Apache on RHEL 5.0

I am in a hosting fix! I have developed a web app for my organisation that allows sharing, interacting, etc. I want to DEPLOY IT ON LAN. BUT... I don't want the end user to type: ...
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Working DNS-DHCP combo for LAN

Can anyone recommend a working DNS-DHCP combo for a small mixed-platform LAN? Preferably one where hosts can be assigned IP addresses and/or names with a web-GUI. The typical DHCP package on Linux ...
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can ping google dns, but not google.de -> unknown host // worked in another network

I have a Laptop with debian jessie installed. At my home network, i could connect successfully to the internet (ping google.de successful). At the external network, i can't ping google.de (result: ...
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How can I (re-)connect DNS for gmail on Linux Mint?

Let me refer responders to this thread on Linux Mint forums: Chrome/Firefox not loading Google websites I've seen this four times in the past two weeks or so. The loss of connection does ...
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Browsers doesn't see an aliases in /etc/hosts

A firm where I'm working uses an internal site with documentation and etc. where all references made e.g. to «srv-moss» — this names should be defined in hosts file, where I did added it. It works ...
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How to change the name of localhost to a custom name which is available to other users in LAN

I need to use the a custom URL name which is accessible from all devices in a LAN. I know that it can be set in the /etc/hosts file 127.0.0.1 myname 127.0.1.1 system09-System-Product-Name # The ...
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Is this the correct SPF DNS TXT syntax to allow the existing email servers (DNS MX records) and to authorize the new smtp server ip-address?

v=spf1 +mx ip4:65.1.2.3 -all Domain DNS TXT records to change: product1.com : sales@product1.com otherproduct.biz : sales@otherproduct.biz Information: Both domains have DNS MX records, and ...
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URL with hostname doesn't work but it works with IP Address

I have a very basic question here. This thing is puzzling me a little bit. I have one Ubuntu machine which is running 12.04 and I am connecting to that machine from putty in my desktop (which is ...
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How to detect particular system call called or not in a whole workflow?

EDIT No. 1 My task is mirroring , i.e., copying updated data from master server to all mirrors, by using rsync and rsh. But during rsync and rsh, I found some delay. My thinking is , the reason for ...