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60

The short answer is to your specific question of listing CNAMEs is that you can't without permission to do zone transfers (see How to list all CNAME records for a given domain?). That said, you can use dig to list the other records by doing: dig +nocmd yourdomain.com any +multiline +noall +answer


36

Try: dig -tAXFR mycompany.com This may or may not work. Many DNS servers will deny a DNS Zone Transfer like this. For more information, see How the AXFR protocol works


22

Do not use .local. Do not use .anythingyoujustmadeup either. Don't even use the reserved TLDs. Use a real domain or sub domain and just don't allow it to be visible to the outside world. The main reason for this is when you work for company A that uses .local (or example.com) and they buy company B that also uses .local (or example.com). Not a lot of fun ...


21

You really would be better off setting up a pair of nameservers if you can. I've never really seen a situation where you couldn't replace a cumbersome hosts file situation with a couple of DNS servers (Really, they are easy to setup and run). However, to answer your question, you can use something like either puppet or cfengine to keep these in sync. ...


18

ipconfig /all will show you the location of your DHCP server. There's a line item that says "DHCP Server" If you want to use ninja skills, you can use the command ipconfig /all | find /i "DHCP Server"


17

Keep track of the time you spend updating /etc/hosts files, deploying the changes and keeping them in sync.


15

It is generally considered a good practice to serve localhost, 0.0.127.in-addr.arpa and the RFC-1918 reverse zones on your internal DNS system to prevent sending queries from them out to the internet. It saves time (you get replies for those queries quickly), bandwidth (no requests leaving your network for zones that shouldn't exist), and relieves the load ...


15

For the record: you can also do this with BIND, but it's a litte more involved. You need to configure bind as the authoritative nameserver for the specific resource record you want to override. For example, if you wanted to redirect gamestats2.gs.nintendowifi.net to your own host, you would need this in your named.conf: zone ...


14

The first thing you should know is that Active Directory and DNS are so intertwined that they're almost one. For all intents and purposes, you should forget the idea of having an Active Directory domain which doesn't have a primary DNS server for Windows clients. I won't say it's "impossible", but I will strongly advise you that it's a path with only pain. ...


14

You can also use host DNS lookup utility with -l switch: host -l domain.com Of course you need DNS zone transfer rights for this to work.


12

When you outsource to another company, especially one that is doing it for free, you might consider what they are getting out of it. Google is in the information business, and they are getting another aspect of your (or your user's) traffic pattern. If I were at a university that used google's name service, I would be raising privacy issues pretty darned ...


12

There isn't really a "supported" method of recovering passwords in Windows Server 2003. If there's no critical data on the machine or in the newly-created domain it would be easiest just to level the box and start over. Edit: I don't mean to sound trite, but if you just setup the machine leveling it and starting over isn't going to be too hard. Why go ...


12

In today's world, I do not recommend creating new zones with arbitrary top level domains, as these might make it into "official dns" at any point in time. I personally would favor the subdomain delegation scenario, as it seems to be fitting what you try to do. (Consolidate but give control to engineering) Maybe you can even find a web-front-end for MS DNS ...


12

First and foremost, make sure you own the domain.tld you plan on using (mit.edu). Even if this never connects to the internet, that's not the point. There are huge benefits to having a hierarchy of dns that at least somewhat matches the org. I've only seen this done when there is someone/people to manage that department in terms of IT support. This is in ...


11

Do not use an invented TLD. If ICANN were to delegate it, you would be in big trouble. Same thing if you merge with another organization which happens to use the same dummy TLD. That's why globally unique domain names are preferred. The standard, RFC 2606 reserves names for examples, documentation, testing, but nothing for general use, and for good reasons: ...


10

A much easier command to remember (and more informative) is: > dig google.com ANY Which returns the following: ; <<>> DiG 9.8.3-P1 <<>> google.com ANY ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 31013 ;; flags: qr rd ra; QUERY: 1, ANSWER: 22, AUTHORITY: 0, ADDITIONAL: 3 ...


8

How about creating a DNS entry for "expenses.mycompany.com" that sends to a webserver with a redirect rule of expenses.mycompany.com -> mycompany.com/expenses? As long as clients have a DNS suffix of "mycompany.com" set they will convert "expenses" into expenses.mycompany.com, and hit that webserver. It means a few extra DNS entries, and some virtual hosts ...


8

+1 for MikeyB's answer. As an extension, how would you convince a corporation that they need anything else? (How to justify the need for a new rack or switch, etc.?) Compare the alternatives, and provide a cost/benefit analysis for each option. It really doesn't take that long to setup a reliable DNS solution. Beyond the test necessary to update ...


7

You've configured the client to lookup against your internal DNS for its primary, and an external DNS server as a secondary? You have a race condition; if the internal DNS happens to be too slow to respond, then the client gets an unusable response from the public DNS server. ping is using the cached response from the lookup against the external DNS ...


7

While not exactly what you're after, why not use a URL shortener on your internal servers? Then you can setup a virtual host on your server that hosts the URL shortener, and do something like: http://go/expenses http://go/tracker The URL shortener would rewrite that to your necessary internal URL. There is an example of a .NET URL Shortener here. The ...


7

resolv.conf specifies the nameservers for resolver lookups, where it will actual use the DNS protocol for resolving the hostnames. Typically the hosts file is used for administrative purposes such as backend and internal functions, which is substantially more isolated in scope, as only the local server will reference it it. /etc/nsswitch.conf specifies the ...


7

There's actually a lot going on here, but much of it may be irrelevant to your situation. First, using DNS master/slave relationships allows easy replication across heterogeneous server types. I know I've synced a primary OS X Server (BIND?) server with Windows DNS. This also allows you to specify that a secondary DNS system may retrieve from different ...


7

The master/slave configuration (also known as “zone transfers,” AXFR or IXFR) is the standard configuration used by most DNS servers. For that reason alone, it’s what I’d recommend, even though it’s complicated. Although I recommend it for interoperability, and because it’s easy for other admins to understand, that doesn’t mean it’s technically the best way ...


7

I wouldn't use .local unless you understand how zeroconf works, as it will become a bigger deal when you start to see IPv6 move into the mainstream. In the past, I've used: Made up TLD (not a good practice for a variety of reasons) Internal subdomain (ie. corp.example.com) Internal domain with a different TLD (ie example.net) IMO, either of the latter ...


7

Never rely on whether your app will be internal or external. Always develop as though the audience of the app will be outside your control (because it is). Go with ENV.APPNAME.DOMAIN.TLD With www. as the alias for "production".


6

No, you should not add RFC1918 IP addresses to public glue records. There are a few reasons for this: If your internal hosts use a DNS server outside the LAN where the RFC1918-addressed authoritative nameservers are, a SERVFAIL will result for obvious reasons It adds garbage to the set of glue records It will have unintended consequences if a resolver in ...


6

DNSMasq does this nicely. It is a pretty light weight DNS server. A config that looks like this might be close to what you want. # go.com requests server=/go.com/192.95.16.109 # all other requests server=8.8.8.8 server=8.8.4.4


6

I think there is some inconsistencies in your design, since you cannot convert a DNS primary zone into a Active Directory integrated zone if that zone is not stored in a Domain Controller. On the other side there is no way to allow only secure updates on a zone if that zone is not an integrated zone in Active Directory. I think that having redundancy is a ...


6

As Gerald Combs pointed out .local is a reserved domain and should not be used other than intended. As Gerald Combs pointed out the .local domain is used by a lot of Apple (and others) software and therefore using it in another way could cause problems with this software. Why not use a subdomain of your public site? Something like ...


6

As that server is clearly not being stressed I'm inclined to think that there is no reason to change anything. The network you have described really doesn't need internal DNS and not having it may even slow (briefly?) down the hacking attempts by the students, as it will not be immediately obvious what machine does what. As you have given no indication at ...



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