IP Address Problems

dan hentaidan at gmail.com
Mon Jan 9 21:24:56 UTC 2006

On 09/01/06, Michael J. Lynch <mlynch at gcom.com> wrote:
> dan wrote:
> Ok..first of all are you using static or dynamic IP addresses?


> If dynamic, your ISP's DHCP server is what assigns the IP address
> and that's the address you should use regardless of what it is.

Thats what I thought, but I got a phone call this morning saying that
every time I connect my computer is assigned a new IP address (looking
through syslog shows the lease to be ~8 days).  I connect a half dozen
times a day and supposedly the bloke in charge gets an email every
time a new address is used and I am using up the avaliable

But I have been connected to the same network since October 2005, and
supposedly this has only been happening in the last few weeks or so,
so I think someone has done something they shouldn't have.

> If static, the file /etc/network/interfaces is what assigns your
> IP address.  Just change this file if you want to change your IP
> address.  Use "ifdown" to take your interface(s) down and "ifup"
> to bring interface(s) up.  BTW - Your ISP is what assigns the IP
> address you should be using here too.
> Spoofing a MAC address is also done via the /etc/network/interfaces
> file.  Try:
>         man interfaces
>         man ifup
>         man ifdown
> These will show you how to do all of what you want *properly*.

Thanks for the info; that's the last time I trust wikipedia ;-)

> There is no need to deconfigure eth0 before shutdown.

If I dont and leave the cable plugged in, it connects and gets the
"wrong" IP address, and the tech support emails inbox gets filled up,
I get a phone call etc.


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