These were Linux (mandrake) machines that were having the drop outs. 
I've actually made them static and we've not had a drop out since.

But yeh from the ipconfig on an XP box, it appears to be 10 minutes.

Anyway, I can increase this ?

Cheers

Phil

 > -----Original Message-----
 > From: Christiaens Joachim [mailto:jchristi at oce dot be]
 > Sent: Wednesday, 12 November 2003 7:56 PM
 > To: 'Phil Greenway '
 > Cc: 'm0n0wall at lists dot m0n0 dot ch'
 > Subject: RE: [m0n0wall] DHCP Server - Expiry ?
 >
 >  You can check that on the clients (in windows 2000/XP: ipconfig /all)
 >
 > Joachim
 >
 > -----Original Message-----
 > From: Phil Greenway
 > To: m0n0wall at lists dot m0n0 dot ch
 > Sent: 11/11/03 4:15
 > Subject: [m0n0wall] DHCP Server - Expiry ?
 >
 > Hi,
 >
 > Can you please advise how long it takes for the DHCP server's IP
 > addresses it gives out to expire ?
 >
 > I'd just like to increase it, we're have a few dropouts here.
 >
 > Regards,
 >
 > Phil Greenway
 >
 >
 >
 >
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