Solved

How does DNS work on a LAN w/no server?

Posted on 2012-12-29
8
359 Views
Last Modified: 2013-01-25
We have a single server with a static IP address that acts as a file server.  No DNS, no DHCP.  We have a DLink DIR-655 router as well that does the DHCP.  All the other clients have dynamic IP.

When pinging the server by IP address, there's a response.  When pinging or trying to reach it by hostname, there isn't a response.  All the dynamic clients are working with both their hostnames and IP addresses.

Manually entering in an entry to the host file of a client alleviates the problem of reaching the server via hostname, but any idea why the computer suddenly can't be reached by hostname?  I thought it was the router.  Isn't my router supposed to have a cache for local DNS?
0
Comment
Question by:epichero22
8 Comments
 
LVL 90

Expert Comment

by:John Hurst
ID: 38730231
A D-Link is a simple consumer router and you do not have DNS working on your server. So you have no option here but to use the HOSTS file to use hostnames. Your D-Link (and most entry level routers) won't do this.

.... Thinkpads_User
0
 
LVL 90

Expert Comment

by:John Hurst
ID: 38730234
If your server is not a domain server, make sure everything is on the same workgroup. Also make sure the server is on the same subnet (it should be).

It occurs to me that if your server *is* a domain server, then you should be able to access it by hostname.

... Thinkpads_User
0
 
LVL 11

Author Comment

by:epichero22
ID: 38730248
Well it worked for several months, then two weeks ago, all the clients couldn't reach the server.  So yes, I updated the Host file, and it worked.

I thought the router managed DNS.  Other host names work when you ping them.  What's up with that?
0
 
LVL 90

Expert Comment

by:John Hurst
ID: 38730256
Perhaps do a TCP/IP repair on your server. Look up Microsoft Support for your particular server for TCP/IP repair and follow the steps.

Also, simply restarting the server may make it accessible again.

The router is managing external DNS and I don't think that has any effect here.

.... Thinkpads_User
0
Highfive Gives IT Their Time Back

Highfive is so simple that setting up every meeting room takes just minutes and every employee will be able to start or join a call from any room with ease. Never be called into a meeting just to get it started again. This is how video conferencing should work!

 
LVL 14

Assisted Solution

by:bfason
bfason earned 250 total points
ID: 38730262
You are most likely recieving internal name resolution through netbios. It is enabled by default on windows operating systems for backward compatability and provides host name resolution to computers in the same broadcast domain. The router most likely assigns DNS settings to the client via DHCP which are usually the same ones the router receives from the isp.

Quick way to determine is open a command promtp and type "ipconfig /all" on a workstation

Under each adapter you will see the dns server assigned and also see if NetBios over Tcp/ip is enabled.
0
 
LVL 18

Expert Comment

by:Akinsd
ID: 38730508
Every home based router runs DHCP and DNS by default. You wouldn't be able to access any website without DNS.

To answer your question; you were using DNS assigned to your router by your ISP. DHCP normally would update DNS entries using dynamically. The router also pulls a DNS suffix from your ISP eg (hsd1.ca.comcast.net.)

Check the domain name on your router. Also run ipconfig /all on any workstation and see what the primary DNS suffix is.

Your server most likely is using a FQDN (Fully Qualified Domain Name) eg. if the dns suffix is "hsd1.ca.comcast.net" and your server host name is epichero22, then the FQDN of your server would be epichero22.hsd1.ca.comcast.net..

That most likely is what the router has for your server in its table. Editing LMHost files (LAN Manager Hosts files)  simply bypasses DNS name look up for that entry. Computers check their host files before querying a DNS server.

Hope that helps
0
 
LVL 8

Accepted Solution

by:
gsmartin earned 250 total points
ID: 38730713
As mentioned, NetBIOS is installed by default.  When use try accessing the file server by name in a UNC path this is referred to as a NetBIOS name.  NetBIOS resolution can only happen in anyone of the following three ways:  1) Through WINS, which requires a server running the WINS server service that will dynamically updates the WINS database with NetBIOS/computer names.  2) Resolve NetBIOS/computer names via the local LMhost file on each workstation and server.  This is a manual file that would need to be updated on all systems as systems are added and removed from the network.  3) Resolve NetBIOS names via an elected Master Browser (through the Computer Browser service) within a workgroup or domain.  The Master Browser is typically the highest level/version workstation or server operating system on the network, which can change as systems are added or removed from the network.  Note all systems need to reference the same workgroup/domain name for anyone of the systems to see each-other.

Since you weren't using DNS or Host files then you weren't resolving hostnames, which require FQDN either by pointing systems to a DNS server or by using a local host file on each system.  

My recommendation and preference, if possible, is to promote your file server to a DC and/or add a at least one dedicated Active Directory server to run DNS and DHCP.  This would easily resolve your issues and provide a centralized logon AD services Domain environment.   The systems can then will automatically update DNS bus DDNS; which is configured by default on all systems.  Make sure to add forward lookup DNS servers for external DNS resolution.

As long as DNS is implemented WINS won't be required; assuming you are running Windows 2000 Server or later in Native mode.  Hopefully, something more recent i.e. Windows 2008 R2 or later.
0
 
LVL 8

Expert Comment

by:gsmartin
ID: 38730735
Corrections:   Ignore - "use try" in second sentence.  When accessing the file server....

Sorry, for some of the typos created by me an my iPhone.

bus = via  ...when talking about DNS and DDNS
0

Featured Post

Free camera licenses with purchase of My Cloud NAS

Milestone Arcus software is compatible with thousands of industry-leading cameras for added flexibility. Upon installation on your My Cloud NAS, you will receive two (2) camera licenses already enabled in the software. And for a limited time, get additional camera licenses FREE.

Join & Write a Comment

Suggested Solutions

So, you're experiencing issues on your network and you've decided that you need to perform some tests to determine whether your cabling is good.  You're likely thinking that you may need to spend money which you probably don't have on hiring/purchas…
Transparency shows that a company is the kind of business that it wants people to think it is.
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
This video gives you a great overview about bandwidth monitoring with SNMP and WMI with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're looking for how to monitor bandwidth using netflow or packet s…

747 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

13 Experts available now in Live!

Get 1:1 Help Now