Open DNS

What views does anyone have on Open DNS?

I've seen references to it before, and have just read this recommendation.

I use Google, they all provide a similar service.

Google Public DNS

It works... but if your ISP runs a properly set-up DNS service there's little point in swapping.

If doesn't (and many don't!) then it may well be worth using.


That's for the free "home" version, if you use (and pay for) the business version then the extra control and security options may well make it worthwhile.

I've been using it for over 3 years. It has been most effective in controlling junior's surfing habits. I'm sure it will continue to work until he realises he can put his own dns server addresses in to his laptops connection parameters.

I'm mainly curious.

In the Network Pane of my PB, under the TCP/IP tab for Airport, there are two DNS Servers listed, and in parentheses alongside it says (Optional).

I vaguely remember entering them some time ago, probably on the advice of someone at Zen.

In reply to a post by Jethro_Tombs:

I've been using it for over 3 years. It has been most effective in controlling junior's surfing habits. I'm sure it will continue to work until he realises he can put his own dns server addresses in to his laptops connection parameters.

Block outgoing port 53 in your routers firewall if you want to prevent this.

Normally you'd just put the router's LAN address in there and rely on it picking up your ISP's DNS servers when you log in.

I tried the OpenDNS servers against my ISP's own (putting them in the router, not the computer)... the primary was slightly quicker than OpenDNS, the secondary was slightly slower.

And I mean slightly, sub-millisecond, which could easily have been due to traffic variations.

So I just let the router pick them up from my ISP.

In reply to a post by billford:

Normally you'd just put the router's LAN address in there and rely on it picking up your ISP's DNS servers when you log in.

I think that's what the Intel iMac does (10.6.8)

We've got an AEBS. In its TCP/IP tab it shows 10.0.x.x by default.

In reply to a post by billford:

If doesn't (and many don't!) then it may well be worth using.

That's the operative point! Many ISP's DNSs fail from time to time.

Best defence is to mix-and-match 1 ISP DNS with 1 public DNS.

I've been using OpenDNS for a long time now ... I think I changed because there were problems with O2's own DNS servers at one point. Don't know if this is still the case. I actually have OpenDNS and Google public DNS configured with O2's primary 5th as my router doesn't allow me to delete this.

Never had any DNS problems but then I have 3 different providers with 5 servers configured.

Once upon a time, the route to the BBC (for iPlayer etc) used to depend on whose DNS you were using (different ISPs saw different addresses, as a means of load balancing). Does that still apply, e.g. what does nslookup return for www.bbc.co.uk. See below.

And if it does still depend on whose DNS you are using, does it make much difference to anything?

For surfing performance, you can get an objective view of whether it makes any noticeable difference to browsing performance from the surfspeed tests at www.numion.com which set off a string of customisable pseudo-browsing tests and tell you how long it took.

Choice of DNS shouldn't make any difference in principle to bulk data transfer that looks up an address once and then just gets on with it. But if the destination address changes depending on whose DNS you are using, the speed may change too.

On Plusnet, with the router hiding the Plusnet-supplied DNS:

nslookup www.bbc.co.uk
Server: home.gateway
Address: 192.168.0.1

Non-authoritative answer:
Name: www.bbc.net.uk
Address: 212.58.244.67
Aliases: www.bbc.co.uk

In most circumstances you won't have problems with using the router - but sometimes there can be issues if a router's implementation of DNS isn't particularly good. if you have issues then specify the DNS servers to see if it resolves the problem.

ta,
Phil.

DNSBench ( http://www.grc.com/dns/benchmark.htm ) is a good way to compare the fastest DNS servers for you. When I was on BE, openDNS was one of the fastest, but from BT it is often well down the list. That said, the difference between the top few is pretty much academic.

DNSBench will also give an indication of whether servers intercept some names. There are various reasons good and bad why they may do this, and whether such interception is appropriate for your needs.

In reply to a post by StephenTodd:

DNSBench ( http://www.grc.com/dns/benchmark.htm ) is a good way to compare the fastest DNS servers for you. When I was on BE, openDNS was one of the fastest, but from BT it is often well down the list.

Doesn't seem to be a Mac utility.