On 8/7/2013 4:53 PM, Sean Alexandre wrote:
On Wed, Aug 07, 2013 at 09:29:57PM +0200, Slavko wrote:is your network like this, please: ------------- | ISP | ------------- | | ------------- | modem | ------------- | ------------------------------ | | | ------------- ------------- ------------- | Debian I | | Debian II | | TP-Link | ------------- ------------- ------------- or like this? ------------- | ISP | ------------- | | ------------- | modem | ------------- | | ------------- | TP-Link | ------------- | ------------------ | | ------------- ------------- | Debian I | | Debian II | ------------- -------------My network is like your first diagram, but with only one machine connected to the modem at a time.
Getting a public address from a private DHCP server is not wrong. The DHCP server may have been given those addresses by the upstream server for allocation. That takes a load off the upstream server.
One thought. Just because there is only one machine connected at a time does NOT mean the previous DHCP lease has been released. It may still be considered active by the DHCP server.
For instance - if you hook up one machine and get a least, that lease may be good for an hour to a week (or more). If you hook a second one up, that may also get a lease for the same amount of time.
Then if you disconnect the first two (or even disconnect the first machine before connecting the second machine) and only have two leases available, you will see this problem.
The cable company was not necessarily incorrect when telling you to power off the cable modem then powering it back on. This will probably reset all leases.
What happens if you do power the cable modem off like they said then power it back on, followed by connecting only the failing machine?
And BTW - you said all of the computers have different MAC addresses. I would hope so! Hardware MAC addresses for a port are unique in the entire world - every one HAS to be different. Of course some OS's allow you to override the hardware MAC address, but that's another story.