> On Sat, 28 Jul 2001, Eric Boo spake: > > > Hi all, > > > > I'm using pump on SID. My ISP is a cable provider who do not issue > > static ips. Usually, when I use pump, I have the same ip address for > > months, unless I switch off the modem and someone else grabs it. > > > > When I reboot into windows on the same machine, I get another ip > > address, then when I go back to linux again, it's back to the same old > > ip address again (assuming no one grabbed it). If I use dhcpcd, it's > > another ip. > > > > Question: How are these ip address stored, if they are (under pump > > espcially), and how do I force pump to get another different ip if > > needed? Here's the deal: Your computer gets a lease from the dhcp server. The lease is for a specific period, for example, 3 days. Halfway through the lease period, your computer's dhcp client should automatically request that the least be renewed, so you get a new 3-day lease. _Typically_ if you never shut down, your TCP/IP address will never change.
When you run Windows, you can see the lease details via WINIPCFG or IPCONFIG. The former is a gui utility built into Win95/98/Me. The latter should be run from the WinNT/2K cmd shell. (Try IPCONFIG /ALL). Both of these tools allow you to release or renew your lease manually. I'd love it if someone would reply and post the Linux equivalents, I behind on my RTFMing. Likely, your computer automatically tries to renew the lease each time the eth0 interface starts up (eg, every reboot or running ifup in Linux. The current OS _probably_ looks like a different computer to the DHCP server. If the other OS's lease hasn't expired, it'll naturally give you a different address because it thinks you're a different system. How are the addresses stored? That's up to the DHCP client, Windows and Linux probably do it differently. If they have a current lease, they'll keep using it. If the lease has expired while that OS wasn't running it should try to get a new lease as soon as it starts up, and it's going to take whatever the server gives it. The DHCP server controls the lease period and whether the server attempts to reserve expired leases. HTH, Paul
