bind ip to subdomain - linux

i have a linux client which uses pppoe to connect to the internet and
everytime this client comes online I wanna bind his ipadress to a subdomain.
dyndns is not an option due to their TTL.
It looks like i have to setup my own nameserver on my root server to accomplish this task because I cannot create the keys needed to run an nsupdate on the client with a provider nameserver... am I correct?
If so is there a good Howto for setting up a bind server for this specific task?

I havent ever maintained pppoe but if it uses dhcp to provide the ip address to the client, you could do updates from the dhcp to the dns.
Instructions on how to do this for debian here: http://www.debian-administration.org/article/Configuring_Dynamic_DNS__DHCP_on_Debian_Stable
Do not thou that you can adapt these to other distros too. You can find the same software atleast on fedora and ubuntu, difference is only how you install the required software.

One posibility is to set their machine to register with somebody like DynDNS. They have all the software you need to automatically notify them when they come online/go offline. This will give them a domain name of something like whatever.homelinux.org (it does not really matter). You then put static CNAME entries in your DNS to point your nice domain names eg southern.company.com to point to whatever.homelinux.org.
When they come online the domain will start to resolve and stop when they go off line since DynDNS have low TTL for this very reason. You can use large TTL in your zone file since the CNAMEs will not change.

Well dont you just need to create an A-Record for this IP on your DNS Server?
If your domain is 'google.com' and you wanted your host to be called 'server1'. Create an A-Record for 'server1' and point it to your machines IP.
Unless I am misunderstanding what you are asking for help with.

Related

2 DNS records point to the same address, but only 1 works

I am using Advanced Zone Editor in cPanel to have 2 addresses point to the same IP (my home ip). There is one (mc.tthread.com) that works flawlessly. On the other hand, i made a record yesterday (testing.tthread.com) to point to the same ip, and that doesn't seem to work. I realize that it takes a couple of hours for the DNS servers to update, but i believe 1 day is more than enough.
Both addresses share the same settings (Type 'A', TTL '14400').
Also, is there a way to minimize the time it would take the DNS servers to update their records?
Thanks for the answers
There is no way to minimize the downtime overall but if this is for some testing/development then what you can do is to use DNS HOSTS hack & override the IP given by your DNS server to that of your need on your workstation.
DNS HOSTS hack file is at: /etc/hosts (Linux) C:\WINDOWS\system32\drivers\etc\hosts (Windows)
Using Google's DNS server will may work sometimes too.
You can use whatsmydns to have a track of DNS propagation: https://www.whatsmydns.net/#A/testing.tthread.com

Wide area service discovery via bonjur / avahi

I'm looking into wide area service discovery and bonjur / avahi seem to be really good.
However, I'm a bit confused about how all this works?
So:
I have a bunch of services running in a cloud.
I have clients which can be located anywhere in the world.
I want the clients to automatically discover the services in the cloud.
I need the clients to be absolutely zero conf, so they don't know IPs, ports, nothing.
If I understand it correctly, this can be done using the above mentioned dns-sd libs. I have full access to a DNS server, so I suppose, the services can register themselves on startup using these libs and then the data can be spread through DNS servers world wide.
The clients can obtain the advertised info by querying the DNS record of my domain using bonjur / avahi tech, right?
All I need to do is to link the client with bonjur / avahi libs, and tell it which domain it should use (query).
Is this correct?
Am I missing something here or is it how this works?
Thanks in advance!
Avahi does not currently support publishing to a wide-area server, though it can browse wide-area. So if you can dynamically update a DNS server somewhere with the appropriate records Avahi would be able to see it.
You do however potentially have more problems to solve here including port mapping/nat traversal which Avahi does not address at all.

Windows Active Directory Domain setup remotely through univention using samba4

I have a slight problem bit of the back story. recently ive been trying to test out univention which is a linux distribution with the goal of being able to replace Microsoft active directory.
I tested it locally and all went reasonably well after a few minor issues i then decided to test it remotely as the company wants to allow remote users to access this so i used myhyve.com to host it and its now been setup successfully and works reasonably well.
however
my main problem is DNS based as when trying to connect to the domain the only way windows will recognize it is by editing the network adapter and setting ip v4 dns server address to the ip address of the server hosting the univention active directory replacement. although this does allow every thing to work its not ideal and dns look up on the internet are considerably longer. i was wondering if any one had any ideas or have done something similar and encountered this problems before and know a work around. i want to avoid setting up a vpn if possible.
after initially registering the computer on the domain i am able to remove the dns server address and just use a couple of amendments to the HOST file to keep it running but this still leads to having issues connecting to the domain controller sometimes and is not ideal. any ideas and suggestions would be greatly received.
.Michael
For the HOST entries, the most likely issue is, that there are several service records a computer in the domain needs. I'm not sure, whether these can be provided via the HOST file or not but you'll definitely have authentication issues if they are missing. To see the records your domain is using issue the following commands on the UCS system.
/usr/share/univention-samba4/scripts/check_essential_samba4_dns_records.sh
For the slow resolution of the DNS records there are several points where you could start looking. My first test would be whether or not you are using a forwarder for the web DNS requests and whether or not the forwarder is having a decent speed. To check if you are using one, type
ucr search dns/forwarder
If you get a valid IP for either of the UCR Variables, dns/forwarder1, dns/forwarder2 or dns/forwarder3, you are forwarding your DNS requests to a different Server. If all of them are empty or not valid IPs then your server is doing the resolution itself.
Not using a forwarder is often slow, as the DNS servers caching is optimized for the AD operations, like the round robin load balancing. Likewise a number of ISPs require you to use a forwarder to minimize the DNS traffic. You can simply define a forwarder using ucr, I use Google on IPv4 for the example
ucr set dns/forwarder1='8.8.8.8'
The other scenario might be a slow forwarder. To check it try to query the forwarder directly using the following command
dig univention.com #(ucr get dns/forwarder1)
If it takes long, then there is nothing the UCS server can do, you'll simply have to choose a different forwarder from the ucr command above.
If neither of the above helps, the next step would be to check whether there are error messages for the named daemon in the syslog file. Normally these come when you are trying to manually remove software or if the firewall configuration got changed.
Kevin
Sponsored post, as I work for Univention North America, Inc.

How to make a Wamp server installed on VPS hosting accessible by a domain name?

I have a VPS hosted server with Windows Server 2003 on which I installed WAMP server, it is working and I am able to access it by localhost and modify it's contents with no problems. Also I have a domain name, say "domain-name.com". My question is how can I make it accessible on the internet by typing my owned domain name in browser?
This is quite an open question, but here goes:
You'll have to set a DNS record that points to your server. Your domain registrar may offer a DNS services themselves. If they do not, and only allow you to set nameservers, have a look at http://dns.he.net (a free DNS hosting service). In the latter case, don't forget to configure the nameservers in your domain registrars panel to the HE DNS servers (ns1.he.net - ns5.he.net)!
The records you will have to add are as follows:
An A record for www.domain-name.com, pointing to your IP
A CNAME record for domain-name.com (often represented in a DNS panel as #), pointing to www.domain-name.com
Optionally, MX and SPF/TXT records if you wish to use e-mail services on your domain/server (this is a whole separate subject to deal with, especially SPF records can be tricky)
Additionally, while this is not part of the question - please don't use WAMP for public/production servers. WAMP was made for development server setups, and it will be configured as such. If you really can't set up a HTTPd+PHP+MySQL setup yourself, then at least have a look at XAMPP, which is more suitable for live servers.

How to create more than one .local address pointing to my mac

I currently have one .local address (Bonjour) pointing to my mac in my intranet, mbp.local, configured in system preferences with the computer name. I use this to send my boss links to demos on my local server (he sits in a chair behind me : >).
I'd like to be able to create new .local addresses to send different demos to my boss (demo1.local, demo2.local, etc) so that I can switch to different working copies to do other work while the demos are still live.
I'd know how to setup Apache to route these requests to the right places, but am unsure if it's possible to make new addresses that point to my mac (I think this has to do with multicasting?).
I have a dynamic IP in my intranet but would be able to setup a static IP if required.
Are you talking about web site demos? I'm not sure I understand the problem. If they're web sites, I'm sure you already know you can simply use a single address with different urls, eg, http://mbp.local/demo1, http://mbp.local/demo2, etc. If it is something else entirely, you can use the Mac's local host file to point multiple fqdns to a single IP address on your local network, but it would be best to have a static IP. Alternatively, you could edit your DNS or WINS server to do the address translation.
I haven't done this myself, but I wonder if you could use what's documented here to start. The difference would be that you'll send your boss links to http://demo1.mbp.local and so on.
I found more about this on this thread on SuperUser.

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