DNS sometimes slow

[TransAmDan]

When you request a page from the website, you computer goes off to find what IP address (house number) the website lives at. This is called looking up the DNS. In some places in the world, and even from my work computer this DNS lookup can take a couple of seconds, it should be 100 times faster, and most of the time it is.
I'm adding the details to a couple of other DNS servers I control so it is a bit of redundancy, and should help improve speeds too.
However we shouldn't have downtime, but there is a chance I miss something and we will be down for a bit.

 

[AmericanThunder]

Have you considered the OpenDNS servers?

 

[TransAmDan]

I have come across many, Google does one aswell. These are cached results from the DNS server. I'm not sure if the delay on the website is caused by the DNS loo up on the server or not, when the Windows hosting one has kicked in that will reveal some results.

I could change the DNS at work to the OpenDNS server, but as its seems the slowest, I will do some testing on that, as many people around the world will be stuck on the DNS thats supplied by their ISP, which may or not be slow too.

Over the last few hours I've been running some server tests too, have a plug-in on the web server that collates timing results. Things like the database lookups are completing in under 1ms. Complete pages served in under 100mS. I don't know how much faster I can make the pages as vBulletin isn't exactly optimised for performance. So if I can improve look up times it should all help the user experience.

 

[saleen 192]

it was very slow this morning around 5ish

 

[AmericanThunder]

The trouble is, many IPS's intercept your DNS requests. How many times these days do you see a "page 403 not found error" when you inadvertantly type a wrong address or click a link that has wrong address? Not often, as many ISP intercept these failures and give you page simliar to "sorry, we couldn't find the page you requested - did you mean xxxxxxx?"
These DNS intercepts result in slow-downs (as they try to give you a meaningful page back) but also break many other functions, VPN's for example.
I can state with certainty that googles DNS servers (as much as it pains me to recomend Google!!), do not do this. Give 8.8.8.8 a try.

 

[TransAmDan]

it was very slow this morning around 5ish

I have logging turned on now, so next time that happens I can go back to take a look. Thanks for letting me know though.

Dave, yeah I know what you mean, you rarely see the 403 or 404 messages now, tend to be encapsulated in the ISP's page. I've used 8.8.8.8 in the past, seems okay. I ran some tests at home, a program you can download which tests all your recent webpages lookup against a whole list of DNS servers to find out what is best for you at your location. Turns out in my case, the virgin media ones (my ISP) were faster than all the others.

I have 3 NS records pointing to 3 DNS servers active for the club website, it will take a day or so for it to propagate, Then I can run some of the previous tests from certain website tools to see if the DNS lookup has improved.