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Forum Discussion

dragonflymr's avatar
dragonflymr
Icon for Cirrostratus rankCirrostratus
Dec 07, 2015

Parsing IP to extract subnet

Hi,   I wonder if there is more elegant and fastest way to extract specific part of IP - like get only part of IP up to second dot, third dot.   I know that I can use scan to separate IP in fou...
devops
iRules
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Kai_Wilke's avatar
Kai_Wilke
Icon for MVP rankMVP
Dec 08, 2015

Hi Piotr,

 

the "best solution" will strongly depend on how often you've to contruct the $newaddr on a single TCP connection.

 

1.) Using the [scan] command to split an IP into octets will cost more cpu cycles than transforming the IP using the [IP::addr] command. So for a single transformation the [IP::addr] command should be used.

 

2.) Using a [scan] command once during CLIENT_ACCEPTED and then substitute different subnet variations and/or perform this action on multiple consecutive HTTP_REQUEST would be faster than calling [IP::addr] multiple times.

 

Cheers, Kai