NetComm modems/routers reject unrecognised leases in a way that confuses 'dhclient'

Simon Hobson dhcp1 at
Thu Mar 17 11:12:45 UTC 2011

Xavion wrote:

>For that reason, I thought you might want to add a workaround in 
>your code to treat such a response as a rejection, before requesting 
>a new lease.

Or, better still, tell people to complain to NetCom about their 
broken software. Failing a fix, use a large axe to reprogram the 
router and get something that isn't broken.

On startup the client should be making a request for any lease it 
still holds. Any DHCp servers on the network should either :

1) Shut the f*** up if they aren't in a position to do something useful
2) Replay with a DHCP-Nak if the address isn't valid for the network/
3) Replay with a DHCP-Ack if the address is valid and the client is 
allowed to use it

Anything else is just broken and you can't expect a client to have to 
work out which of the many ways a server can be broken when the 
specific function of the DHCP service is to configure the client. 
Working around blatently broken stuff merely legitimises it and means 
it will never get fixed.

Simon Hobson

Visit for books by acclaimed
author Gladys Hobson. Novels - poetry - short stories - ideal as
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