To add some filter rules in conf file

Simon Hobson dhcp1 at
Mon Oct 19 12:21:03 UTC 2009

First off - please fix your mailer - it's isn't quoting material very 
clearly. Also, please stop crossposting to dhcp-users at which 
is an old list address and merely forwards to 
dhcp-users at (making duplicate messages as it goes).

Ashmath Khan wrote:
>That's correct, I have the same understanding. But the issue is this:
>I have a series of rules to be run in order, if a rule is met, then 
>stop. It would be something like this:
>rule1: match a string in vendor option, select a pool etc
>rule2: match a different string in vendor option
>rule3: if vendor option doesn't exist select a pool etc
>rule4: see if client falls in the h/w address range, select a pool etc.
>rule5: see if client has requested for so and so option
>So, I can't put all denies in one pool, like you did below.
>If dhcpd doesn't currently support this, I need to do code changes 
>to move further. Can you or somebody suggest me, if you have already 
>worked on making changes ? or is there any other separate list which 
>has dhcpd developers(may not be the actual owners) ? or is there any 
>other GPL based dhcpd for Linux ?

No idea about the code - you'll have to grab the source and take a 
look. Just be aware before you start that there are some very subtle 
nuances with DHCP that are easy to fall foul of.

I do have one last idea, though if it will work or not I don't know. 
If you check "man dhcp-eval" you'll find there is an "if ... elseif 
... else" mechanism. I could see the possibility of using this to set 
a variable to say how far a client matched your sequential list of 
tests - so you could drop out the test with a variable set to "r1", 
"r2" etc. Then configure your classes with match if <somevariable> = 
"r1" and so on.

Finally - what are you actually trying to achieve ?

Simon Hobson

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