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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Moving up DNS domain between webhosting servers

first post over here. Until yesterday I had a virtual shop working in a VPS webhost site, but because of the quality of service it was decided to move the whole webapp to another webhost, in a ...
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How to define DNS server in openvpn?

I setup an openvpn server with static key (certificate mode is not usable due to DPI at the national gateway), but I cannot successfully change the DNS automatically after the connection. I searched ...
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No DNS resolution after upgrade from ubuntu 14.04 to 16.04

I upgraded ubuntu 14.04 to ubuntu 16.04 and I have a problem with the internet connection. Specifically, DNS after update stopped working. For debugging purposes I set the only DNS 8.8.8.8, but name ...
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Debian cannot resolve hostnames

I have a problem resolving host names on Debian running on vmware. It just stopped working out of the blue. Somewhere after uninstalling percona server and deleting /etc/mysql . Initially it thought ...
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No internet connection after update from ubuntu 14.04 to 16.04 [duplicate]

Is there anyone who may help me with the following problem? I upgraded ubuntu 14.04 to ubuntu 16.04 and I have problem with the internet connection. Secifically, DNS after update stopped working, I ...
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pointing Linux DNS server from one sub domain to another subdomain

I have DNS server to my domain abc.com. Need to point my sub domain xx.abc.com to another subdomain xx.def.com. As it's hosted in xx.def.com, I will get any IP, so they will provide only subdomain ...
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Connect to commercial VPN on OpenBSD 5.9

I recently installed OpenBSD 5.9 and I'm trying to get it functional enough to use as a replacement for Debian. One thing where I hit a brick wall is connecting to my VPN. I use a commercial VPN which ...
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why samba 4 is giving the following error attempting to join to domain

trying to join windows 7 clients to samba 4 that is using named as name server i am getting the following error: An attempt to resolve the DNS name of a domain controller in the domain has being ...
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Error in named.conf

I am getting the following error: Starting named: Error in named configuration: zone blk1999.lab/IN: loaded serial 2001062501 zone localhost.localdomain/IN: loading from master file named.localhost ...
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Finding out what DNS server are being used

Using dig I can query a specific DNS server for some DNS records, for instance dig example.com A @192.168.1.1 Where in this instance 192.168.1.1 is my router's ip. Is there a way, using dig or ...
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DNS problem > If I disable recursion, I can't ping my result

I have configured dns server, and if i enable recursion, I can ping and got the result. [root@seobd ec2-user]# nslookup google.com Server: 52.10.197.195 Address: 52.10.197.195#53 ...
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dnsbind not working from client end

I am trying to configure dnsmasq in a virtual environment. I have created 2 VMs in VMware Workstation. Was successful in installing and configuring DNS Server and able to do nslookup of client and ...
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Split DNS (bind9), match-clients any doesn't work?

I've been fighting with this for the last few days. A few of my entries have external and internal IP's. My internal network is 10.0.0.0/8. When I nslookup pc1.clase.net internally it responds with ...
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reverse slave DNS server zone file not transferred

I am using amazon free tier with RHEL 7and configuring master and slave dns server. From master everything is ok, but slave I couldn't find result. Also I would like to know how can I secure my dns ...
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What ports need to be open on a firewall to access the internet?

Let's say as the example that I have a firewall that blocks ALL ports from all sources/destinations. What ports would I need to open to be able to successfully run: ping google.com ...and are ...
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Iptables to redirect DNS lookup IP and Port

I have discovered that my ISP (verizon) is intercepting all DNS traffic on port 53. Using iptables, I want to redirect all DNS lookup traffic to a specific IP and Port (5353). Any attempt for my ...
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Website is active but domain name not showing on WhoIs lookup from Linux command-line

I am trying to lookup the WhoIs entry for the following domain: anorien.csc.warwick.ac.uk However, while typing the URL directly into the browser displays a web-page, when I type: whois ...
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why resolv.conf is changing

I have a very strange issue in my Linux machine - Red Hat 6.7 version when I update my resolv.conf file as the following: options attempts:2 options timeout:1 search usa.Pe.corp ...
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From an IP how can I get a DNS entry? [duplicate]

In a bash, I have an IP like 104.16.117.182. This is the address of unix.stackexchange.com. But, from the IP, how can I resolve it to the hostname? Like: >>> magic 104.16.117.182 you get: ...
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Samba4 DNS - clear old DNS records

Creating AD 2003 domain using Samba-4.3.4 with internal DNS. ISC-DHCP as a server. On Debian. DNS updates comes only from DHCP-server. What tool do I have to use to clear old DNS records, or what ...
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1answer
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Configuring FreeBSD to get IP from my FreeBSD DHCP Server

I have a scenario where I have two FreeBSD machines. I setup one to be a DHCP server so it can lease IP address. I have provided IP ranges, default DNS , host name , and all other settings in my ...
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How to proxy nmap and dns resolution of nmap

How to use nmap and dns resolution of nmap over proxy? I tried proxychains, but for dns resolution it doesn't work, it's known bug as I read on some forums. It works well without dns_proxy feature in ...
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I can ping IPs but can't resolve domains

I have Xubuntu 14.04 installed on my server. network-manager is not installed. It seems to have lost its ability to resolve domains, and I'm not sure where to begin diagnosing the issue. ping 8.8.8.8 ...
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top command shows dnss running at 290%

We're running software on a CentOS 6.2 virtual machine and it's been crashing quite a lot lately and keeps running slow. I checked the RAM usage, but that's only using 4GB to 5GB of the available ...
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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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Bind RPZ config with domains of various level

I use RPZ to blacklist some domains and my configuration looks like: *.com A 127.0.0.1 mydomain.net A 127.0.0.1 if i query a whatever domain .com it works correctly giving me 127.0.0.1 let's ...
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DNS server for blacklisting tons of domains and also some TLDs

I'm trying to setup a basic DNS server for my lan that is able to put in a nullroute or 127.0.0.1 lots of domains. The domains I want to block come from a list but I also want to block some domains ...
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1answer
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Configure BIND as Forwarder only (no root hints), encrypted + RPZ blacklist / whitelist all together

My setup is getting more complex, generally I tend to divide things in pieces and assemble them together by myself. But it seems this time I need more help to get the whole gears working together. ...
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What is “Localhost” binding in DNS forwarder in pfSense?

Trying to debug some network problems, I found that my DNS forwarder is configured in the following way: Although many entries stands for my WAN interfaces and LAN stands for LAN one, I don't ...
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How to stop dhclient from updating resolvconf on Debian?

I want to use certain DNS servers regardless of whatever I get through DHCP. I'm trying to configure dhclient to ignore those, but I can't seem to get it to work. Per advice from this article I added ...
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Slow DNS resolve from curl/lynx etc

I have a strange issue with DNS resolving: Root of the problem is that I get curl errors: "Error executing HTTP request: name lookup timed out". Tried to ping some sites, all resolved fine (and fast). ...
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Why does postfix copy /etc/resolv.conf to its chroot too early, causing DNS failures?

Edit: For anyone else having this problem, this question was actually was very badly asked/understood and a better description of the problem (and the correct solution) can be found here. I'm trying ...
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Redhat 7 DNS Bind Failed to restart

I am getting Error while Restarting the Named.service in Red-hat 7 Here is my Lab Status and all the Command. Configure DNS in REDHAT 7 DNS Name p1.linux.com IP address 192.168.1.1/24 N/W ID ...
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Hostname troubles

I am trying to change the hostname on a Linux RHEL6.5 box and have changed it in /etc/hosts and in /etc/sysconfig/network, as I have read.. The command hostname'now returns the new hostname, but ...
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host returns 0 for a non existing name

host usually returns 0 for existing hosts $ host www.google.com ; echo $? www.google.com has address 172.217.16.132 www.google.com has IPv6 address 2a00:1450:400a:805::2004 0 and 1 in case of ...
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How to know where resolv.conf entries come from?

I use resolvconf for nameserver management because my OpenVPN requires it. However, I notice that it generates nameserver information that is not exactly how I would want it: # Dynamic resolv.conf(5) ...
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SSH always connects to the same IP address [closed]

No matter what the host is, SSH keeps trying to connect to 162.13.177.241. Command ssh -v user@host Output debug1: Connecting to 162.13.177.241 [162.13.177.241] port 22. My /etc/hosts file is ...
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Avahi commands not working in CentOS

I want to use Avahi tools for mDNS service discovery in CentOS 6.6. I have installed the following packages: avahi, avahi-tools, nss-mdns. I checked the Avahi daemon and it is running: $ service ...
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How to configure isc-dhcp-server to offer upstream DNS servers?

Every example dhcp.conf I can find has hard coded DNS servers - typically the google public DNS addresses... option domain-name-servers 8.8.8.8, 8.8.4.4; If I leave out the option ...
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How can I make my primary DNS take priority over other servers?

Note - I believe my title is the way it's meant to be... I used dnsmasq on my server and it sets DNS (via DHCP) to clients as: 192.168.2.1 (local server) ISP DNS 1 ISP DNS 2 This at least works - ...
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How can I programmatically modify DNS lookups in real time?

I want to use OpenDNS (parental control) and UnoTelly (geo-restriction circumvention) together. OpenDNS returns an IP to an error page if the site is blocked. So if I get that error IP, then I want ...
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Can sendmail be made to refuse connections if NIS or DNS are down?

We run a sendmail 8.14 server for a domain which has its user database managed in NIS. My nsswitch.conf is pretty vanilla: passwd: compat group: compat shadow: compat hosts: ...
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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 generate SSHFP records?

I need to setup SSHFP records in the DNS for my host. I have done some searching but I haven't found any good example. What are SSHFP records? What does SSHFP records look like? How do I create ...
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sed to change dns log string format

I want to use sed to change the following text: (3)www(5)first(3)nth(6)domain(3)com(0) to: www.first.nth.domain.com Can each group between the parenthesis separators be captured and then ...
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Network has no ping and can't resolve hosts

This is the config on /etc/sysconfig/network-scripts/ifcfg-eth0: DEVICE=eth0 TYPE=Ethernet UUID=c7sdfsdf-dfgdgdfgdgd-dg ONBOOT=yes NM_CONTROLLED=yes BOOTPROTO=static IPADDR=x.x.x.x ...
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Configuring Dynamic DNS on CentOS 7 without dhcpd service

I have a CentOS server on which I configured DNS but it doesn't serve as a DHCP sever, since I have a d-link router which serves as such (DHCP is enabled on it). Is there a way I can configure Dynamic ...
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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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Ethernet Connected But No Internet

I am trying this on Intel Galileo Gen 2 which runs Yocto Linux and I am unable to connect to Internet using Ethernet. I have WiFi card but that doesn't connect as well. I have tried following commands ...
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use ufw to block all incoming/outgoing domain requests except my chosen one

I'm trying to allow port 53/udp to query ONLY to google's 8.8.8.8 and listen from it. I don't want my PC to accept offers from any other DNS. I'm testing this theory by connecting my PC DIRECTLY to ...