What makes a good drop catching script?

[kevinm]

As a new member of nominet and forum lurker here for a while I am now planning to write my own drop catching script for uk domains.

Just for background, I plan to use php (as it is the scripting language I am most comfortable with, and should cope with this task well) on a P4 server with 2 gig ram. I have done some speed tests and it appears to be easily fast enough for the number of queries that can be performed with the DAC.

I am keen to include as many worthwhile features as I am capable of writing and I have listed some of my ideas, but I am keen to see what features you use and couldn't do without, or wish you had.

My list:

• A variable 'throttle' which can vary the queries per second to the DAC (from say 1 per second through to 16 per second, which is close to the maximum allowed over a minute).

• A way to prioritise domains, so a domain identified with a higher percieved value can get a greater share of the DAC requests over a 'normal' domain.

• If a domain is either won or lost, it is automatically removed from the list so DAC request won't be wasted.

• A pre-nom alarm (although I am not sure what this looks like at the moment). Perhaps if the script detects a pre-nom is either won or lost, all requests switch to pre-noms only and the throttle is set to maximum automatically. (This assumes that a whole chunk of pre-noms will drop on the same day)

I am not after trade secrets (although if you want to share...), and all thoughts, ideas and feedback on what makes a good drop catching script is appreciated.

 

[retired member 1]

Scripting is only a small part of what makes a good "dropcatcher" tatics also play a large part.

So long as the script you write does everything you need as fast as possible then you'll be fine.

Don't be suprised if you re-write/modify it many times before you're happy.

 

[A-Wing]

Ideally you want to be using C (or C++ at a push) as you should see a 30 fold increase in responsiveness which is what you want, you can also deamonize it easier. If you have to use PHP at least use something like the eaccelerator module as that should give you at least a 10 fold speed increase.

I can't give away much but there are still several tricks for you to discover.

 

[jonno]

Ideally you want to be using C (or C++ at a push) as you should see a 30 fold increase in responsiveness which is what you want, you can also deamonize it easier. If you have to use PHP at least use something like the eaccelerator module as that should give you at least a 10 fold speed increase.

I can't give away much but there are still several tricks for you to discover.

rubbish. the bottleneck in anyones system regardless of programming language is always nominets dac limits. programming language plays a very small part.

ping is the main factor, followed by tactics and "what you know"

 

[Ellis]

"ping is the main factor"

How do you ping the DAC?

 

[retired member 1]

"ping is the main factor"

How do you ping the DAC?

ping dac.nic.uk

from the server that has dac access

 

[A-Wing]

rubbish. the bottleneck in anyones system regardless of programming language is always nominets dac limits. programming language plays a very small part.

ping is the main factor, followed by tactics and "what you know"

Yes Nom's dac is the major bottleneck, but I should imagine gaining a few extra milliseconds when firing off a request certainly helps.
As a (maybe poor) comparison one of a computer's major bottlenecks is RAM speed, doesn't mean a faster CPU won't make a difference.
Agreed Ping is the main factor.

 

[aqls]

I think they have turned off ping.

At least I can never ping it.

-aqls-

 

[A-Wing]

I would imagine all servers on Nominet's IP range will have the same/similar ping times, one of them may accept one.

 

[Ellis]

ping dac.nic.uk

from the server that has dac access

That's not worked for me for months now - I always used to get a reponse - either from my server or my home pc - now it doesn't respond at all.

wierd!

 

[jonno]

"ping is the main factor"

How do you ping the DAC?

i did not mean ping as in the command ping

The most you can do is get a ping time to nominets firewall. They've probably blocked ICMP packets through their firewall.

Jonno.

 

[Slater]

I've been catching for a couple of months now and am changing my script on a daily basis.

Catching names is a mixture of scripting skill, tactics and good old fashioned luck. I don't think having a super fast PC to run your script will make a huge difference to your ability to catch names even if you were running at 16 queeries a second, not a particularly heavy load for a modern PC.

Don't expect to catch every name you want even if it's the only name you are watching, a vast majority of the good names go to a small number of catchers who seem to have pre-cognitive abilities (and possibly more DAC queeries ).

You'll find you get a real buzz when you do start catching some.

 

[Ellis]

i did not mean ping as in the command ping

The most you can do is get a ping time to nominets firewall. They've probably blocked ICMP packets through their firewall.

Jonno.

I can ping Nominet - no probs!

I was under the impression that Nominet moved the physical location of the DAC servers... is that right

 

[A-Wing]

I can ping Nominet - no probs!

I was under the impression that Nominet moved the physical location of the DAC servers... is that right

There seems to be a couple more hops between nominet's web server(s) and the dac server(s), so you could well be right

 

[retired member 1]

I can ping Nominet - no probs!

I was under the impression that Nominet moved the physical location of the DAC servers... is that right

Yes, this was some time ago...probably when you stopped being able to ping the DAC

They moved it closer to home AFAIK

 

[retired_member16]

Yes they moved it, and its fecked;

7. ge3-0.pr1.lhr1.uk.above.net 0% 68 68 77 76 77 77
8. pos3-0.mpr1.lhr1.uk.above.net 2% 67 68 77 77 77 77
9. 213-152-232-236.available.lhr.above.net 2% 67 68 1 1 1 2
10. host-213-248-206-1.nominet.org.uk 3% 66 68 4 3 4 6


3% packet loss over above.net to the host before the Dac server(s)

 

[A-Wing]

host-213-248-206-1.nominet.org.uk looks like its closest pingable router (assuming it is a router, the IP is a nice round routerish IP )

 

[A-Wing]

I thought I noticed a small packet loss, mine goes straight from my ISP to fe1-1-nom-col1.nominet.org.uk where it takes a left turn somewhere to get to that router 8 hops including my router

 

[retired_member16]

Nope, not going there after all.

 

[Jeewhizz]

5 hops here