Domain Name System (DNS) is a service that provides the resolution of host names to IP addresses.

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UFW is blocking DNS

I am configuring the security in my server. For easier the manage at the firewall, I installed the UFW. I did some settings in the UFW and I allowed some ports. Therefor when I enabled it the DNS ...
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How can I block a subdomain with dnsmasq?

I use dnsmasq as a whitelist on my network. My dnsmasq.conf file looks like this: bogus-priv domain-needed no-resolv server=/stackexchange.com/8.8.8.8 #etc... I would like to be able to block a ...
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689 views

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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2answers
58 views

How to I fetch the very latest DNS records from a recently updated domain?

I recently updated my domain and added CNAME and TXT records, and don't want to wait for the changes to propogate. How can I go directly to the source and query the DNS records to verify everything is ...
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1answer
2k views

How can I use CNAME in Bind properly?

I'm new to Bind/DNS and want to point/map SMTP, webmail and IMAP to my domain but a check in nslookup is failing. How can I nslookup SMTP this way? The error I get is: smtp.stylez24.com: NXDOMAIN ...
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0answers
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rndc addzone failed: not found

I installed bin 9.8.4 (default) on Debian Wheezy. after configuration I tried to add a slave zone with the following command: rndc addzone test.zone '{ type slave; file "test.zone"; masters { ...
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2answers
583 views

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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1answer
85 views

Why DNS server changes when enabling another interface on machine

My system has 6 interfaces, a loopback, a Xen Bridge, and then 4 ethernet interfaces eth0-3. In this system, my DNS server assigned by DHCP on xenbr0 is 192.168.1.1. Initially eth1 is disabled and ...
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2k views

delay to get password prompt when ssh'ing to a public server

i have a server (debian 7) setup in my university with public ip. when I ssh into the system (from outside the campus), I get a weird delay of 5-10 seconds before I get the password prompt. Why is ...
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2answers
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How does DNS name resolution work, in principle?

Right now I'm taking an online course for Linux sysadmin and I was asked a question I just generally don't understand. I know how to search for a name server, if I'm correct at least it's using the ...
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How do I set my DNS on Ubuntu 14.04?

Most of the info I see online says to edit /etc/resolv.conf, but any changes I make just get overridden. $ cat /etc/resolv.conf # Dynamic resolv.conf(5) file for glibc resolver(3) generated by ...
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1answer
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No domain defined in /etc/resolv.conf

I see more and more servers that have no domain defined in the /etc/resolv.conf file. Only a search entry. In what cases is this setup used ? Are there any cases where it must not be used ? ...
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1answer
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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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3answers
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Linux, resolv.conf — adding MSDNS and Bind DNS nameservers where MSDNS isn't recursive?

How to resolve from a non-recursive MSDNS and if not found resolve from googleDNS (recursive)? ## resolv.conf ## nameserver 192.168.10.1 # msdns, non-recursive nameserevr 8.8.8.8 # ...
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2answers
318 views

ping not working for google alone

one of my friend changed some network config in my laptop at home, He said he tried something related to block a website(he tested it with www.google.com).Now www.google.com not loading . Even he dont ...
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0answers
168 views

named.run file deleted but data left on disk?

Today I had a name-server stop resolving DNS due to the /var directory being full from the named.run cache build up. I tried removing all the files using: rm -rf name* However, although running ls ...
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Deliver emails outside network, from a server behind router DNS and port forwarding

I've been trying to configure webserver to deliver emails outside the local network. Server is connected directly to the router and relay on its DNS service, and one of that online service for resolve ...
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1answer
5k views

How to check if port forwarding is enabled?

I have just set up a DNS server for my own network, and many guides online suggest to make sure that port forwarding on port 53 is not enabled. The thing that is not clear to me is this: should I ...
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1answer
1k views

Host home.lan.home.lan not found: 4(NOTIMP) error in bind9 (DNS)

I have been following this guide to set up a DNS server using bind9 on Ubuntu 12.04, but after all the configuration, when I run host -l home.lan I get the following error: ; Transfer failed. Host ...
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1answer
151 views

Make the DNS server update my host name

I have some sort of DNS server running on my router (running Asuswrt-Merlin, and I can run commands from another Linux computer by host name, i.e., ping web-server. However, when I change settings on ...
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3answers
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Ping IP works, nslookup fails. New Kernel

I am compiling my own 3.14 kernel. I fear I may have left out some important networking feature to get DNS working. I can't resolve domain names. I can ping my DNS server. I can resolve using that ...
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1answer
806 views

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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1answer
98 views

NSD Zone file wrong resolution

I've set up NSD with the following zone file: $ORIGIN ldom. ; my "Local DOMain" @ IN SOA lserver root.lserver ( 44 ;serial ...
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1answer
848 views

Cannot install BIND dns with yum on Oracle Enterprise Linux 6.1

I am currently using Oracle Enterprise Linux 6.1 to use for Oracle RAC. However I am stuck at installing BIND (DNS Server) at the VM I've set up. I've used the following command: yum install ...
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0answers
261 views

Postfix/devcot MailServer - not receiving emails

I'm new to linux and unix in general, I've worked with a shared hosting provider over the years where everything was setup for me, including email. I'm now trying to create my own mail server in my ...
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1answer
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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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4answers
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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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3answers
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alternative to nslookup in rhel7?

nslookup does not come preinstalled in RHEL 7 Beta. I noticed even dig and host was not pre installed. I read couple of links which mentions nslookup is dead/deprecated, so is there an alternative for ...
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1answer
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What is the effect of setting the timeout value to 0 in /etc/resolv.conf?

In order to fix a problem with DNS resolution in a particular customer environment, their admin has suggested adding options timeout:0 to the /etc/resolv.conf file on their CentOS 5 server. The man ...
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1answer
301 views

How to check if all of dns resolvers are working? [closed]

How can I check if all of dns resolvers are working under linux console?
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1answer
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CentOS 6 not regestering new hostname on Windows Server 2003

I rebuilt a Windows 7 Workstation with CentOS 6.5. The Windows 7 had a host name aaa attached to domain ddd.local. The new CentOS hostname is bbb. When I try to ping it: $ ping bbb ping: unknown ...
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1answer
24 views

configuration to listen-on different depending on the domain asked

I want to configure bind such that the host served differ depending on the domain asked. the use case is the following: it must respond to anyone if the requested domain is in the domain my server is ...
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0answers
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apt-get update could not resolve addresses [closed]

When I run apt-get update (on Ubuntu 12.04) I keep getting these errors: Err http://security.ubuntu.com precise-security Release.gpg Could not resolve 'false' Err https://get.docker.io docker/main ...
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1answer
75 views

Installing Arch on VM - DNS Issues

I have been following the Install Wiki and I have arrived at the part where I need to install X Server. My issue is that I cant install X because my DNS doesnt work. I can ping 8.8.8.8 just fine, ...
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1answer
552 views

Change the DNS server in etisalat USB modem

I need to use the open DNS : 208.67.222.222,208.67.220.220 in my network connection. I use etisalat 3.75 USB modem HUAWEI in my Ubuntu 12.04 PC. I had tried to add this DNS in : ...
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1answer
86 views

Setting up Bind9 - lsb-base not in sources

I've been having real trouble installing Bind9 following this tutorial http://forums.debian.net/viewtopic.php?f=16&t=39146 When I get to entering these commands: apt-get -y build-dep lsb-base ...
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1answer
186 views

zone delegation in Bind

I have a lot of zones defined in my DNS server. I need to delegate one particular zone to a foreign DNS server and I don't have access to my domain-registrar control panel, currently. Is there a way ...
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3answers
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Configure multiple interfaces with different hostnames using DHCP and DNS

I have a machine running Ubuntu 12.04 Server with two interfaces connected (eth0, eth1) to the network. Our network is set up so that a FreeBSD based DHCP server hands out leases and registers the ...
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3answers
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why host command return no SRV record?

I am a bit confuse here, I'm trying to establish a connection to Active Directory server from linux, someone told me to use this command: host -t srv zeus.company.com Assuming the Active Directory ...
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1answer
565 views

Why does dig take much longer than DNS query time?

I'm investigating slow DNS responses on Ubuntu, I have installed bind9 to improve times from local cache, but still something is odd. What could make dig wait for 10 seconds and say that query time ...
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1answer
234 views

named starts but doesn't answer until reboot

I have a current arch linux arm running on raspberry-pi and bind 9.9.4.P2-1 from the community repository. I'm using this bind as a slave-nameserver for our internal network. I have enabled named ...
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1answer
1k views

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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1answer
208 views

OpenBSD with adsuck: nslookup works, other applications not

(The problem that nslookup works but other applications can't resolve name is asked very often, mainly for windows. I read a lot of these answers but none of them was applicable.) I use OpenBSD with ...
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228 views

Arch wifi keeps dropping

I recently installed Arch, wifi has been messing around. Dropping and generally not connecting. I fixed it by ruling it was DHCP not getting a lease in time, I assigned a static IP and all is good. ...
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1answer
125 views

DNS not resolving using IP rule for dialup modem

I am running Ubuntu 12.04. I have a HSDPA USB Modem, with which I can successfully dial in. It works fine as well when I set the default gateway (remote IP address) in the main routing table. But I ...
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3answers
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Why can't I ping Google?

I can't ping google.com (unknown host). But I can ping IP addresses. I tried to ping the IP address of Google but it doesn't work. resolv.conf nameserver 8.8.8.8 nameserver 209.139.209.33 ...
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Getting Samba 4.1's “internal DNS” to update hostnames from dhcpd

Samba 4 comes with its own "internal DNS" which can be used rather than BIND. Since Samba 4's main new feature is AD replacement, I would figure that its DNS would function similarly to Windows ...
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2answers
234 views

Combining different DNS servers

My company uses DNS servers that provide access to internal systems, for example "build.company.de" is resolved accordingly if one of the internal DNS server is queried. However, the internal servers ...
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1answer
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Why do DNS queries fail if the first nameserver is not recursive?

I have a Linux box (Ubuntu server 11.10) inside a Windows Active Directory domain, and is joined the domain using likewise-open. The resolv.conf file looks like this: domain mydomain.com nameserver ...
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3answers
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How to disable DNS caching or override TTL for a certain hostname?

I've set up my own dynamic DNS service by using a script to automatically update the A record for a subdomain of one of my domains. The host with the dynamic IP address runs, among other things, a ...