Unanswered Questions
2,288 questions with no upvoted or accepted answers
9
votes
2
answers
733
views
Cisco DNS doctoring or Hairpinning?
I've the following configuration: CISCO 881, IOS 15.2(4)M6. On WAN interface is configured the 86.34.156.48/29 subnet from our ISP. Behind the router is staying 2 webserver. NAT: 86.34.156.51 <> ...
- 3,221
9
votes
2
answers
3k
views
DNS and Active Directory configuration for a branch office
We've got a branch office with no on-site services at the moment, and we'd like to change that. The biggest goal is to setup some file servers but faster logins and DNS resolution will be welcome as ...
- 680
7
votes
0
answers
3k
views
Registrar nameservers vs. NS records for bare domain?
OK, I'm a bit new to DNS, but I'm having some trouble finding the answer to this. I have a domain registered at google domains. As with other registrars, you have access to their free DNS, and ...
- 71
6
votes
0
answers
2k
views
Caching, forwarding Bind 9.9.4 server works for weeks, suddenly SERVFAIL on all queries (rebooting fixes it)
I have bind 9.9.5 running on two servers (CentOS 6 and 7), for caching and forwarding DNS queries for a mail server. The servers run fine for weeks, then suddenly respond to all queries with SERVFAIL. ...
- 548
5
votes
0
answers
2k
views
DNSSEC for private internal sub zones of an external domain
Consider the following scenario:
example.com is hosted on CloudFlare and it's signed by CloudFlare DNSSEC. Everything works as expected for example.com.
Inside the company we have some internal ...
- 5,830
5
votes
0
answers
4k
views
BIND: DNS failover and high availability with dynamic updates
I am trying to design a system with 2 servers that act as both DHCP and DNS servers with dynamic updates. I am using ISC DHCP and BIND9.
It looks like this.
Server1 - DHCP primary and DNS master. IP ...
5
votes
1
answer
37k
views
CentOS 7 Unable to Resolve Any Host Names
New to Linux and looking for friendly assistance.
My company is re-configuring our network DNS infrastructure to point our internal DNS servers at two new CentOS 7 / BIND 9 machines in our DMZ ...
CommunityBot
- 1
5
votes
0
answers
3k
views
Understanding (and partially disabling?) DNSSEC for an internal domain
I am setting up a new DNS infrastructure for our internal HPC cluster environment. This involves providing a migration path from our existing DNS authorities and domains.
For sake of example, let's ...
- 226
5
votes
0
answers
4k
views
can't access sub-subdomain: DNS_PROBE_FINISHED_NXDOMAIN
I can't access to sub-subdomains.
For example http://electricien.synerciel.fr is working.
But, for sub-subdomains http://electricite-lemonnier.electricien.synerciel.fr/ returns ...
- 498
5
votes
0
answers
6k
views
Force Windows to use only TCP for DNS lookup
I have a broken (badly configured) VPN network that I cannot change. The remote gateway will route all UDP traffic for port 53 to a special DNS service. But I need to use a different DNS server also ...
- 382
5
votes
1
answer
1k
views
Mac OSX Server 10.6 DNS Issues
The server was upgraded from 10.5 from 10.6, during the upgrade the Reverse Zones were lost so I tried to recreate these but found that it's best to delete all zones, definitions and start again.
So ...
CommunityBot
- 1
5
votes
1
answer
15k
views
curl and wget attempting an ipv6 connection
On my dedicated server (hosted by OVH), that is running a fresh install of Ubuntu 14.04, curl and wget take approximately 10 seconds to complete a simple request.
$ curl -v google.com
* Rebuilt URL ...
CommunityBot
- 1
4
votes
0
answers
247
views
Microsoft DNS listening on a high-numbered TCP port
In addition to port 53, the Microsoft DNS service also listens on a single high TCP port. This port changes every time the service starts (since it is a high port). What is this port used for?
Note: ...
- 141
4
votes
1
answer
1k
views
Windows 2016 DNS server returns SERVFAIL for non-existing domain
I have two DNS resolvers in /etc/resolv.conf file. The top one is Windows DNS server, and the bottom one is my wi-fi router. Please see below.
nameserver 192.168.1.126
nameserver 192.168.1.1
In ...
- 757
4
votes
1
answer
1k
views
Internal DNS TTLs
Four-site company using Windows Domain and DNS servers. Minimum of one DC/DNS server per site. One site is HQ and hosts most companywide servers and services. DNS records for Windows servers are ...
- 903