how to test the scalibity and stabilty of ISC DHCP???

Simon Hobson dhcp1 at
Mon Dec 5 08:00:28 UTC 2011

ameen.shajahan at wrote:

>                 Also how many dhcp entries can ISC DHCP code would support?

AFAIK, that is entirely dependent on your hardware. I believe there 
are users with many 10s of thousands of users.

CPU capacity is rarely a limit.

You need memory to store the in memory tables and hashes - basically 
the more available IPs in pools, the more memory you need. This is 
(IIRC) largely independent of how many of those addresses are 
actually leased.

And then you disk I/O performance to handle the updates. Firstly to 
update the leases file, secondly to handle the logging. This appears 
to be the main constraint people hit.

In terms of testing performance, there are some stress testing tools 
around - hopefully someone will pop up and suggest which to use.

Simon Hobson

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