[Dxspider-support] Node_default spot filtering

[Martin Davies G0HDB]

On 2 Aug 2015 at 23:58, djk wrote:

> One of the rather confusing things about filters is that one can have 
> 'input' and 'output' filters. The default is 'output'. This means that 
> the filter operates on spots emanating 'out' of the node - i.e. to the 
> users or connected nodes. The reason this is the default is that the 
> user is only interesting in stuff coming 'out' of the node to him/her. 
> The 'input' filter will work for the user as well, but it will filter 
> the dx spots that are being sent - an unlikely scenario.
> 
> But for nodes, you have two options:
> 
> 1. You can accept all spots and then provide a user_default filter that 
> does what you want, but allows the user to override it.
> 
> 2. You can filter the spots on input (i.e. rej/spot node_default input 
> ...) which will drop those spots on the floor *on input* with no 
> override possible by a user. The more elegant way requires a bit of 
> lateral thinking: your node is effectively a user on the peer node that 
> you are connected to. So you can set your required filter *on your peer 
> node* with a simple 'rcmd gb7xxx reject/spot ...' and that will prevent 
> any those spots arriving onto your node in the first place.
> 
> Also if I read what you want to filter correctly you actually want:
> 
> reject/spot node_default on hf and by_zone 14,15
> 
> or
> 
> rcmd gb7xxx reject/spot on hf and by_zone 14,15
> 
> Which will reject all hf spots coming from zone 14/15.

Many thanks Dirk, you'll given me exactly the hint I needed to get the input filter working on 
GB7DXC-5 - the secret is in the word "input"!

I was trying to set an input filter on the 'DXC-5 node to "drop on the floor" all spots that don't 
come from zones 14 & 15, ie. all spots from the rest of the world other than from western EU, 
but I hadn't appreciated that it was necessary to include the word "input" in the filter string.

I've now implemented the following on 'DXC-5:

	rej/spot node_default INPUT on hf and NOT by_zone 14,15

and this seems to be doing exactly what I wanted - when I'm logged in to the sysop console 
on 'DXC-5 I only see spots that have been generated by stations in western EU.

It's very helpful to have this sorted out because it will also help me to set a filter on GB7BAA 
for its feed to the existing AK1A-based GB7DXC node that I'm keeping running for the time 
being - I occasionally, eg. during periods of heavy contest activity, use 'rcmd/GB7BAA' to set 
a filter on what spots get fed to 'DXC.

--
73, Martin G0HDB



---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.tobit.co.uk/pipermail/dxspider-support/attachments/20150803/4095c696/attachment-0001.html>