QuickDNS

View the latest, best formatted and most complete version of this manual online at http://mindprod.com/application/quickdns.manual.html.

What is QuickDNS for?

1. It speeds up your browser when it looks up a website.
2. It enables your browser to find critical websites even when your DNS (Domain Name Service) servers are down.

Overview

How does it work? Let me explain with a familiar analogy. When you telephone someone, you either:

• memorise the number.
• look it up in your address book.
• look it up in a paper phone book.
• look it up in some electronic phone book.
• call directory assistance.

When your browser goes to a website, e.g. mindprod.com, similarly, it needs to look up the number to get the IP 65.110.21.43. Your computer does this automatically every time you visit a website by first visiting a computer on the web called a DNS server to look up the name for you.

DNS Lookup vs Hosts. Lookup

1. it adds an extra second or more to fetching a web page. It is a bit like looking up the number in an electronic phone book every time you make a phone call.
2. if there is anything wrong with the DNS server, you are dead in the water, even if the website you want to visit is fully functional.

What you can do is create a little electronic address book of commonly visited websites called C:\Windows\system32\drivers\etc\hosts. The computer does not have to pester the DNS server to get these numbers. You can create this file manually with a text editor such as Notepad. You can manually look up the IPs of your common servers with the ping utility, e.g. on the command line type:

The problem is, from time to time, the IPs change and your browser gets sent to the wrong IP. You need something to keep the list of IPs up to date. That is where QuickDNS comes in. You might run it every week or every time you reboot or every time lookup seems to be failing.

Advantages of QuickDNS

The advantages of using QuickDNS are:

• It saves the overhead of looking up the IP of a website each time you visit.
• It lets you keep on browsing your crucial websites even if there is something wrong the DNS server.
• QuickDNS works with either IPv4 (Internet Protocol Version 4) (e.g. 65.110.21.43) or IPv6 (Internet Protocol Version 6) (e.g. 1080:0:0:0:8:800:200C:41FA ) IPs.
• QuickDNS is designed so that even if you have power failure right just as it is running, no files will be corrupted. Just in case, it leaves behind a hosts.bak file containing the old IPs.

Disadvantages of QuickDNS

• If the IP changes and the old one immediately stops working (which is not usually the case) you will not be able to browse that website until you run QuickDNS to refresh your hosts file. In contrast, ordinary DNS lookup will automatically notice the change within an hour or so.
• Modern Windows is more clever than it used to be. It keeps its own short-term DNS cache of recently visited sites. It does not always have to look up the IP, so you might not notice that much speedup using QuickDNS. How much speedup you get depends on a number of factors including the speed of your Internet connection and how responsive your DNS servers are (you normally have two). The easiest way to find out if QuickDNS buys you anything is to try it. If not, just remove the entries from the hosts file and go back to pure Windows DNS lookup.
• Some sites like google.com have thousands of servers. Every time you look up the domain, they give you a different IP. This way they can balance the loads. If you use QuickDNS to freeze on a particular IP for a day or so, you are defeating that purpose to a minor degree.
• QuickDNS only works on Windows and not on older Windows. It works only on XP, W2003, Vista, W2008, W7-32, W7-64, W8-32, W8-64, W2012, W10-32 and W10-64.
• You have to manually set up the initial hosts. file with a text editor. It is not clever enough to figure out which domains you use most often.
• It requires basic knowledge of files and text editors.

Format of Hosts. File

• In Windows W95, W98 and Me, your hosts. file lives in C:\Windows\hosts.
• In Windows NT and W2K, your hosts. file lives in C:\WINNT\system32\drivers\etc\hosts.
• In XP, W2003, Vista, W2008, W7-32, W7-64, W8-32, W8-64, W2012, W10-32 and W10-64, your hosts. file lives in C:\Windows\system32\drivers\etc\hosts.

You can disable a website with a line like this: 127.0.0.1 google.cn

QuickDNS does not support the older W95, W98, Me, NT and W2K.

Running

rem running QuickDNS
rem adjust drive and directory to match where you put the quickdns.jar file.
J:
cd \com\mindprod\quickdns
java -jar quickdns.jar

and it will check all the IPs and update any that have changed. It will leave alone those marked with #leave. Even when it does not change any IPs, it still tidies up the hosts. file into neat columns. It never changes the order of the entries or removes comments.

If you want to run this bat file automatically, every time you boot, put a shortcut to it in: C:\Users\user\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup\ or use Ace utilities to insert a registry entry to arrange to have it run on boot.

Surprisingly, Windows immediately notices the changes and puts them into effect right away. You don’t have to reboot.

Output

Typical output will look like this:

QuickDNS updated: 173.194.33.40 to 173.194.33.46 for apis.google.com
QuickDNS updated: 173.194.33.55 to 173.194.33.47 for google.ca
QuickDNS updated: 173.194.33.34 to 173.194.33.97 for google.com
QuickDNS updated: 104.20.3.47 to 104.20.2.47 for statcounter.com
QuickDNS updated: 173.194.33.38 to 173.194.33.36 for translate.google.com
QuickDNS updated: 159.33.3.85 to 23.3.105.160 for www.cbc.ca
QuickDNS updated: 23.6.98.234 to 23.6.162.234 for www.paypal.com
QuickDNS made 7 updates to your C:\Windows\System32\drivers\etc\hosts file.

If you don’t see any output and you invoked with the shortcut quickdns.jar instead of java.exe -jar quickdns.jar, chances are you have *.jar associated with javaw.exe instead of java.exe. javaw.exe hides output.

Caveats

Make a back up copy of C:\Windows\system32\drivers\etc\hosts.. The hosts. file is fairly fragile and mysteriously becomes corrupted fairly often. Just copy your backup onto the damaged C:\Windows\system32\drivers\etc\hosts. and run QuickDNS. If that fails, reboot and repeat.

Windows 10

QuickDNS does not work under Windows 10 unless the bat file that invokes it has the run as administrator option. This is because Windows 10 now locks the hosts. file as a system file.

Acquiring QuickDNS

Download information for QuickDNS

Package	Version	Released	Licence	Language	Notes
QuickDNS	1.1	2016-05-31	free	Java	❘ precis ❘ manual ❘ screenshot ❘ browse source repository for the current version of QuickDNS. Refreshes IPs in hosts. file. 177K zip for QuickDNS Java source, compiled class files, jar and documentation to run on your own machine as an application. Runs on any OS that supports Java e.g. W2K, XP, W2003, Vista, W2008, W7-32, W7-64, W8-32, W8-64, W2012, W10-32, W10-64, Linux, LinuxARM, LinuxX86, LinuxX64, Ubuntu, Solaris, SolarisSPARC, SolarisSPARC64, SolarisX86, SolarisX64 and OSX. First install the most recent Java. To install, extract the zip download with WinZip, (or similar unzip utility) into any directory you please, often J:\ — ticking off the use folder names option. To check out the corresponding source from the Subversion repository, use the TortoiseSVN repo-browser to access quickdns source in repository with [Tortoise] Subversion client on wush.net/svn/mindprod/com/mindprod/quickdns/. After you have installed the jar, you can run it as an application. Type: java -jar J:\com\mindprod\quickdns\quickdns.jar parms adjusting as necessary to account for where the jar file is. download ASP PAD XML program description for the current version of QuickDNS. $1989.00 US donated so far. If the CMP utilities solved your problem, please donate a buck or two, or donate to one of the charities featured in the footer public service ads throughout the website and get a tax receipt. QuickDNS is free. Full source included. You may even include the source code, modified or unmodified in free/commercial open source/proprietary programs that you write and distribute. Non-military use only.

standard footer

	This page is posted on the web at:	http://mindprod.com/application/quickdns.manual.html
	Optional Replicator mirror of mindprod.com on local hard disk J:	J:\mindprod\application\quickdns.manual.html
	Please read the feedback from other visitors, or send your own feedback about the site. Contact Roedy. Please feel free to link to this page without explicit permission.
	Canadian Mind Products IP:[65.110.21.43] Your face IP:[18.188.246.157]
Feedback	You are visitor number